Author Topic: AMS-2 (Alpha Magnetic Spectrometer)  (Read 47239 times)

Offline Moe Grills

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AMS-2 (Alpha Magnetic Spectrometer)
« on: 05/16/2011 07:54 PM »
   I hope I'm not jumping the gun.
I'm confident that  Endeavour will successfully deliver this Alpha-Magnetic Spectrometer science package to the ISS.
Fingers crossed? Or knees bowed?
:)
Now about the AMS itself.
After it's attached to the space station, what precisely will it be looking
for?
I confess I'm no particle physicist; and there appears to be conflicting info on different sites.
1) It's either looking for high-speed alpha particles.
2) Or anti-matter particles.
3) Or "Dark Matter"?

I'll probably get humiliated here by my ignorance of particle physics;
oh well. :(  Everyone has to eat humble pie at one time or another.
« Last Edit: 05/18/2011 04:24 PM by Aobrien »

Offline AnalogMan

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This might be a good place to start:
http://www.ams02.org/

Offline rdale

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I _highly_ recommend going to the NASA Youtube or John44's archive site and grabbing the press conference from the first attempt. There was a very good explainer, with graphics and research, showing what AMS will do. Also Analog's post is perfect with their homepage.

Offline axmor61

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I have a question regarding the MLI that covers the AMS-02 top radiator. Will the MLI blanket with the lettering AMS be removed or is a permanent blanket?
Thanks.

Offline Space Pete

I have a question regarding the MLI that covers the AMS-02 top radiator. Will the MLI blanket with the lettering AMS be removed or is a permanent blanket?
Thanks.

It is a permanent blanket and won't be removed.
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Offline axmor61

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Thank you Space Pete.

Offline Moe Grills

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I _highly_ recommend going to the NASA Youtube or John44's archive site and grabbing the press conference from the first attempt. There was a very good explainer, with graphics and research, showing what AMS will do. Also Analog's post is perfect with their homepage.

Thanks. Those are some interesting links and info.
I also hope for some serendipitous discoveries by such instruments.

Offline Aobrien

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AMS-2 (Alpha Magnetic Spectrometer)
« Reply #7 on: 05/17/2011 07:50 PM »
Changing the title as you shouldn't start a thread saying that we need to start one. Next time please just use a regular title.
NSF L2=The Ultimate Space Passport

Offline Moe Grills

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #8 on: 05/18/2011 05:25 PM »
Changing the title as you shouldn't start a thread saying that we need to start one. Next time please just use a regular title.

Good point. Thanks.

As for the AMS-2?
She has arrived at the ISS this morning.

Latest I have is is that she's still on schedule to be handed off arm to arm and installed on the station on Thursday.

Online dsobin

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #9 on: 05/19/2011 06:11 PM »
I've checked at the www.ams02.org website and I can't find any status info. The last post on their website says it will launch May 17, which is rather old news. They are using twitter, but the tweets are, of course, not very detailed.

Does anyone know of a better site which is posting more in-depth status of activation/checkout?

Thanks.

Offline rdale

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #10 on: 05/19/2011 06:38 PM »
That would probably be the best spot. My guess is they are busy doing activation / checkout ;) Make sure you listen to today's presser with the early info.

Offline marsavian

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Offline Moe Grills

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #12 on: 05/19/2011 11:32 PM »
   There are two websites I understand:
one for the general public; and one for professional scientists.
I'll see about posting the URL's

Yes! The AMS-2 is now permanently installed on an ISS truss.
It draws about 2500 Watts of power from the station's power supply
now. That's quite a lot.

  I also learned that the instrument will indeed be attempting to detect
antimatter particles, and maybe dark matter as well, if dark matter can be detected by these means.

 

Offline Moe Grills

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #13 on: 05/19/2011 11:39 PM »

The AMS-2 website for professional scientists is
http://ams.cern.ch/

 For the general public, it's:
http://www.ams02.org/

Offline TheFallen

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #14 on: 05/21/2011 10:54 PM »
Nice photo of AMS and starboard truss taken during EVA-1

http://spaceflight.nasa.gov/gallery/images/shuttle/sts-134/flightday05/ndxpage2.html
« Last Edit: 05/21/2011 10:56 PM by TheFallen »

Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #15 on: 05/22/2011 12:17 PM »
An update on where we stand with AMS data collection from today's (FD-7's) execute package:

Quote
AMS continues to operate on ISS nominally. Yesterday, AMS received ~50 million events and collected 90 Gb of data! This is more data than expected!

WOW! :o ;D
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Offline Moe Grills

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #16 on: 05/27/2011 07:58 PM »
Nice photo of AMS and starboard truss taken during EVA-1

http://spaceflight.nasa.gov/gallery/images/shuttle/sts-134/flightday05/ndxpage2.html

I'd select that for photo of the week.     :)

Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #17 on: 06/18/2011 07:57 PM »
From ISS On-Orbit Status Report for 18/06/2011.

Weekly Science Update (Expedition Twenty-Seven/Twenty-Eight -- Week 12)

AMS-02 (Alpha Magnetic Spectrometer): Each day, AMS continues to collect about 100 Gigabytes of data from 40 million cosmic rays, over 2 Terabytes of data & 1 billion events to date. Temperatures good during high Beta owing to shading by port array. Thanks for power cycle.
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Offline AnalogMan

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #18 on: 06/26/2011 09:38 AM »
Update from the AMS website:

HAPPILY COLLECTING FROM THE CERN POCC
June 25th, 2011

Three hours after AMS-02 was installed on the International Space Station on may 19th, it get used to its new life in the Space and started detecting particles smoothly and continuously: at a rate of about 50 millions of cosmic rays/day it has already taken more than one billion of events! While the spectrometer was happily collecting particles in space, the AMS-02 team managed to transfer the Payload Operation Control Center (POCC) from JSC – Houston to a new building at CERN – Geneva.


Full article at http://www.ams02.org/2011/06/happily-collecting-data-from-the-cern-pocc/

Offline bobthemonkey

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #19 on: 06/26/2011 08:27 PM »
Can anyone confirm that the ACOP system for AMS-02 didn't fly in the end (this was the onboard data recorder with 2xRAID1 arrays) and was instead replaced with nothing more than a Thinkpad with an extra HDD. This did fly, but I'm not sure if it was a replacement for ACOP, or in addition to.

Thanks.

Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #20 on: 07/20/2011 01:56 PM »
A great AMS-02 video:

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Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #21 on: 09/05/2011 05:45 PM »
From AMS via Twitter:

3.5 months onorbit we are still learning new things about operations. Large ISS radiators have more affect on AMS than originally thought. Only minor issue from radiators. All other operations are nominal. Potential smaller crew on ISS will not stop AMS science operations.
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Offline CP

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #22 on: 09/09/2011 10:44 AM »
Any details?

Offline rdale

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #23 on: 09/09/2011 11:36 AM »
Details about what?

Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #24 on: 09/10/2011 09:16 PM »
From ISS On-Orbit Status Report for 10/09/2011.

Weekly Science Update (Expedition Twenty-Eight -- Week 25)

AMS-02 (Alpha Magnetic Spectrometer): All AMS payload and laptop ops are nominal. The component that has been near its temperature limit is doing better, and AMS worked with JSC and MSFC flight control teams to reposition the STRRJ to determine the thermal affect on this component. When the STRRJ was positioned at 40 degrees so that it presented more surface area to that particular side of the AMS payload (and less deep space - much colder), the component warmed up. This was seen previously as the STRRJ transitioned from -8 to 25 degrees, and was confirmed again in this 25 to 40 deg transition.
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Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #25 on: 09/20/2011 05:30 PM »
An AMS update from @AMSISS via Twitter:

As of this morning, we are at 5,577,145,060 events (tracked particles) since we arrived on the ISS. Everything is operating as expected.
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Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #26 on: 09/29/2011 08:32 PM »
From @AMSISS via Twitter:

AMS exceeded 6 billion recorded events today!
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Offline Nomadd

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #27 on: 09/29/2011 08:52 PM »
From AMS via Twitter:

3.5 months onorbit we are still learning new things about operations. Large ISS radiators have more affect on AMS than originally thought. Only minor issue from radiators. All other operations are nominal. Potential smaller crew on ISS will not stop AMS science operations.

 It would be interesting to know if the effect from the radiators is a matter of miscalculation or of an actual unexpected effect on the particles themselves. It would be the difference between fine tuning and scientific data.

Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #28 on: 11/02/2011 08:42 PM »
Check out the new cosmic ray counter! :)

http://ams.nasa.gov
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Offline Moe Grills

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #29 on: 11/03/2011 08:34 PM »
Check out the new cosmic ray counter! :)

http://ams.nasa.gov


Cool!

Offline Tcommon

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #30 on: 11/04/2011 02:49 AM »
Check out the new cosmic ray counter! :)

http://ams.nasa.gov

where is the dark matter counter?

Offline rdale

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #31 on: 05/23/2012 07:27 PM »
International Space Medicine Summit 2012: Day 2 Part 6 -- Alpha Magnetic Spectrometer

May 19, 2012

Physicians and biomedical scientists gather to discuss space medicine research at this annual conference organized by the Baker Institute and Baylor College of Medicine.


Offline Danderman

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #32 on: 05/24/2012 12:56 AM »
Can anyone confirm that the ACOP system for AMS-02 didn't fly in the end (this was the onboard data recorder with 2xRAID1 arrays) and was instead replaced with nothing more than a Thinkpad with an extra HDD. This did fly, but I'm not sure if it was a replacement for ACOP, or in addition to.

Thanks.

I assumed that ACOP didn't fly because it required a mid deck locker space that sort of disappeared from the manifest.

Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #33 on: 07/25/2012 02:01 PM »
AMS experiment marks one year in space

Geneva, 25 July 2012. CERN today marked the Alpha Magnetic Spectrometer's first year in space with a visit from the crew of the shuttle mission, STS-134, that successfully delivered AMS to the International Space Station (ISS) just over a year ago. Launched on 16 May last year, the detector was already sending data back to Earth by 19 May, and since then, some 17 billion cosmic-ray events have been collected. Data are received by NASA in Houston, and then relayed to the AMS Payload Operations Control Centre (POCC) at CERN for analysis. A second POCC has recently been inaugurated in Taipei.

"The AMS detector has so far achieved everything we expected of it," said Nobel laureate and AMS spokesperson Samuel Ting. "That's a great credit to the team that put the detector together, and the team that installed it on the ISS. We're honoured to have them here today to celebrate AMS's fist year in space."

The STS-134 mission was the last flight for space shuttle Endeavour, crewed by commander Mark Kelly, pilot Gregory H. Johnson and mission specialists Michael Fincke, Greg Chamitoff, Andrew Feustel and European Space Agency (ESA) astronaut Roberto Vittori. The AMS detector's first year in space has been a learning curve: data have been used to calibrate the detector and fully understand its performance in the extreme thermal conditions encountered in space.

"Among AMS's achievements is that for the first time, we've been able to identify electrons with energies exceeding 1 TeV before they enter the atmosphere," said Ting. "This holds out great promise for the AMS research programme that's now getting underway."

Kelly, along with Ting, CERN Director-General Rolf Heuer and ESA Director for Science Alvaro Giménez Cañete held a press conference at the AMS POCC before a tree-planting ceremony at which a commemorative plaque was unveiled in the lawn outside the POCC. In the afternoon, the astronauts will give a presentation for over 200 undergraduate summer students from 71 nations who are currently at CERN to get a taste of life in research.

"It's a real privilege to visit CERN today, and we're proud to have played a part in launching the AMS experiment's fascinating research programme," said Kelly. "Meeting some of the young summer students who represent the future of science and engineering was a highlight."

http://press.web.cern.ch/press/PressReleases/Releases2012/PR20.12E.html
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Offline IRobot

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #34 on: 07/25/2012 10:25 PM »
I really hope that the AMS will debunk the dark matter theory. I can't understand how so much time and money is spent on a single theory to explain mass discrepancy! Even something as recent estimates of inter stellar density reduce the "need" for unseen matter.

Offline hanschristian

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #35 on: 07/26/2012 01:25 PM »
I really hope that the AMS will debunk the dark matter theory. I can't understand how so much time and money is spent on a single theory to explain mass discrepancy! Even something as recent estimates of inter stellar density reduce the "need" for unseen matter.

well in that case, theory debunked, or proven, I'll be happier to donate some of my hard earned money to spend it "on a single theory to explain mass discrepancy"

here's one that is very happy that the AMS is up there...
« Last Edit: 07/26/2012 01:26 PM by hanschristian »
The Sky is NOT the Limit...

Offline bolun

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #36 on: 08/09/2012 03:37 PM »
http://www.esa.int/esaHS/SEM54OSX55H_index_0.html

Quote
In one year, AMS-02 has recorded more than 17 billion particles.

The huge amount of information is sent via satellite to the USA and then through optical cables to the control centre run by the European Organization for Nuclear Research, CERN, in Switzerland.
 
Everything is stored for analysis. Every hour, the centre receives 240 gigabytes of information for archiving – about the size of a typical consumer hard disk.

The control centre also monitors the instrument’s vital signs, keeping its temperature stable despite being subjected to its surroundings swinging between –30ºC to +40ºC in the harsh space conditions.

Subatomic particles are extremely small and proving their existence requires extreme precision. AMS-02 is constantly calibrated to guarantee true readings. For example, the particle detector used to tell electrons from protons can be adjusted by as little as three-thousandths of a millimetre.
 
At this level of accuracy, natural events such as solar flares can add errors and the mission controllers at CERN need to allow for them during calibration.

The centre never closes: “Scientists are working round the clock looking at particles that affect us all the time,” says Maurice Bourquin, professor at the University of Geneva and founding father of AMS-02.

The control centre was formally opened on 25 July by the NASA astronauts who flew AMS to the Station. They unveiled a plaque and planted a tree with principal investigator Prof. Samuel Ting and CERN director Rolf-Dieter Heuer to mark the occasion.

Offline IRobot

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #37 on: 08/09/2012 10:36 PM »
Check out the new cosmic ray counter! :)

http://ams.nasa.gov

where is the dark matter counter?
It's the buffer holding "zero".

Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #38 on: 10/01/2012 05:01 PM »
AMS HADRONIC TOMOGRAPHY
September 29th, 2012

Operating in the International Space Station since May 2011, AMS is performing very accurate measurements of cosmic ray (e.g. Proton and Helium nuclei) with unprecedent sensitivity.

This picture represents a “tomographic” reconstruction of the AMS top-of-instrument material obtained using the Proton-to-Helium flux ratio.
Tiny changes of the interaction probabilities of these nuclei with different materials are used to trace the material inhomogenities. Detector elements such as screws, electronics boards, and mechanical interfaces are clearly recognizable.

http://www.ams02.org/2012/09/ams-hadronic-tomography/
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Offline Big Al

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #39 on: 11/23/2012 12:44 AM »
So to sort this out, the dark matter recorder hasn't recorded any thing. So the dark matter end of things is nothing, on to the next theory.
So am I right adout this ? Nobody has come out and said this, but I assume it's true

Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #40 on: 11/23/2012 01:13 PM »
So to sort this out, the dark matter recorder hasn't recorded any thing. So the dark matter end of things is nothing, on to the next theory.
So am I right adout this ? Nobody has come out and said this, but I assume it's true

Not exactly, no.

It is my understanding that AMS has seen a few interesting things regarding the dark matter theory - however there hasn't been a definitive announcement yet.

So I wouldn't say that the dark matter theory is "dead" yet. But if dark matter is there, it isn't obvious, either.
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Offline IRobot

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #41 on: 11/23/2012 11:04 PM »
IMO, the only way the dark marker counter moves over zero is if a cosmic ray hits the memory spot where counter is stored...

Although the AMS was one of the largest cost slips I've seen (50x!), I think it will money well worth if it finds nothing and puts thousands of scientists working on something else other than dark matter.


Offline hop

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #42 on: 11/24/2012 03:20 AM »
So to sort this out, the dark matter recorder hasn't recorded any thing.
There is no specific "dark matter recorder". AMS just records some basic characteristics of particles that run into it. Some models of dark matter predict excesses of various normal particles, so they could stand out compared to what is predicted from other sources. However, there are many uncertainties in the other possible sources, so definitively attributing a specific excess to dark matter may be very difficult. The PAMELA results should give an idea of how this sort of thing can play out.
Quote
So the dark matter end of things is nothing, on to the next theory.
AFAIK AMS is not expected to be able reject every dark matter model.
Quote
So am I right adout this ?
I don't believe so.
Quote
Nobody has come out and said this, but I assume it's true
A robust negative result would be almost as big news as a positive one. If either happens, you'll hear about it. The fact that the AMS team has been so quiet (about everything, not just dark matter) suggest their analysis is still in progress.
« Last Edit: 11/24/2012 03:21 AM by hop »

Online eeergo

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #43 on: 03/14/2013 06:01 PM »
A very interesting presentation on AMS-02, both engineering- and physics-oriented, was given yesterday at the Neutrino Telescopes 2013 meeting in Venice:

https://agenda.infn.it/sessionDisplay.py?sessionId=9&confId=5268#20130313

Second presentation (appropriately titled)
-DaviD-

Offline mlindner

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #44 on: 03/14/2013 07:21 PM »
Check out the new cosmic ray counter! :)

http://ams.nasa.gov

From the source of the web page.

         <!-- -------------------------------------------------------------------- -->
         <!--                         Cosmic Ray Counter                           -->
         <!-- -------------------------------------------------------------------- -->
         <!--   This counter is a simulation of the real-time measurements.        -->
         <!--   It is seeded in hidden field lastEventCountValue by realistic      -->
         <!--   count values as of the date in lastEventCountDate.  The algorithm  -->
         <!--   used to make it count faster then slower, then faster again is a   -->
         <!--   simulation to show how the measurement rate changes over time.     -->
         <!-- -------------------------------------------------------------------- -->
« Last Edit: 03/14/2013 07:22 PM by mlindner »
Internal combustion engine in space. It's just a Bad Idea.TM - Robotbeat

Offline mlindner

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #45 on: 03/14/2013 07:28 PM »
Also unless I missed something. Why is everyone here against such a well accepted theory like dark matter? Heck, I didn't even realize there were many people that didn't accept it.
Internal combustion engine in space. It's just a Bad Idea.TM - Robotbeat

Offline a_langwich

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #46 on: 03/14/2013 07:37 PM »
Also unless I missed something. Why is everyone here against such a well accepted theory like dark matter? Heck, I didn't even realize there were many people that didn't accept it.

Everyone?  Only one poster, if I read the thread correctly, spoke against it, and one other asked if it was dead.  Sample size too small to reach significance.

Offline AnalogMan

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #47 on: 03/28/2013 07:59 PM »
First Results of the AMS-02 experiment to be presented on April 3rd at CERN
March 28th, 2013

Nearly two years after the launch of STS134,  after collecting and analyzing more than 25 billions of events,  the  AMS Collaboration will release  the first physics results from  the Alpha Magnetic Spectrometer on the ISS.
 
Prof. Samuel Ting will  talk  at  CERN  Main Auditorium (Bldg. 500-1-001)  on Wednesday, April 3rd,  2013 at 17:00.
 
It will be possible to follow this event in real time using the CERN  webcast service.
http://webcast.web.cern.ch/webcast/

Offline Bubbinski

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #48 on: 04/03/2013 04:43 AM »
There's a press conference tomorrow live on NASA TV about results from AMS.  Bill Gerstenmaier is one of the presenters, and several other high ranking people are listed. 

http://www.nasa.gov/home/hqnews/2013/apr/HQ_M13-054_AMS_Findings_Briefing.html

Just what did they find out about dark matter?  Did they confirm it?  It's got to be pretty big and important, I would think.
I'll even excitedly look forward to "flags and footprints" and suborbital missions. Just fly...somewhere.

Offline AnalogMan

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #49 on: 04/03/2013 03:58 PM »
Its all about positrons!

AMS COLLABORATION
Press Release     April 3rd, 2013, Geneva, Switzerland  (download pdf)
 
First Result from the Alpha Magnetic Spectrometer (AMS) Experiment
 
The Alpha Magnetic Spectrometer (AMS) Collaboration announces the publication of its first physics result in Physical Review Letters. The AMS Experiment is the most powerful and sensitive particle physics spectrometer ever deployed in space. As seen in Figure 1, AMS is located on the exterior of the International Space Station (ISS) and, since its installation on May 19, 2011 until the present, it has measured over 30 billion cosmic rays at energies up to trillions of electron volts. Its permanent magnet and array of precision particle detectors collect and identify charged cosmic rays passing through AMS from the far reaches of space.  Over its long duration mission on the ISS, AMS will record signals from 16 billion cosmic rays every year and transmit them to Earth for analysis by the AMS Collaboration. This is the first of many physics results to be reported

[... continues]

http://www.ams02.org/2013/04/first-results-from-the-alpha-magnetic-spectrometer-ams-experiment/
http://www.ams02.org/wp-content/uploads/2013/04/Press_AMS_en.pdf
« Last Edit: 04/03/2013 04:00 PM by AnalogMan »

Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #50 on: 04/03/2013 04:15 PM »
STS-134's legacy delivers already! :)
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Offline Lee Jay

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #51 on: 04/03/2013 04:17 PM »
Its all about positrons!

Oh good.  All those negatrons have been getting me down.

"AMS has measured the positron fraction (ratio of the positron flux to the combined flux of positrons and electrons) in the energy range 0.5 to 350 GeV. We have observed that from 0.5 to 10 GeV, the fraction decreases with increasing energy. The fraction then increases steadily between 10 GeV to ~250 GeV. Yet the slope (rate of growth) of the positron fraction decreases by an order of magnitude from 20 to 250 GeV. At energies above 250 GeV, the spectrum appears to flatten but to study the behavior above 250 GeV requires more statistics – the data reported represents ~10% of the total expected. The positron fraction spectrum exhibits no structure nor time dependence. The positron to electron ratio shows no anisotropy indicating the energetic positrons are not coming from a preferred direction in space. Together, these features show evidence of a new physics phenomena."

I love this sort of thing!
« Last Edit: 04/03/2013 04:17 PM by Lee Jay »

Offline Ben the Space Brit

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #52 on: 04/03/2013 05:38 PM »
Well, if nothing else, at least it's something we can point to and say: "This is something the ISS has done that we could not have done elsewhere!"
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Offline John44

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #53 on: 04/03/2013 07:00 PM »
NASA Science Advisory: Alpha Magnetic Spectrometer Results
http://www.space-multimedia.nl.eu.org/index.php?option=com_content&view=article&id=8188

Offline MP99

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #54 on: 04/03/2013 07:55 PM »
I had not appreciated that AMS had the potential to resolve the dark matter issue. Exciting.

Really hoping AMS gets to resolve this question - ASAP!

cheers, Martin

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #55 on: 04/03/2013 08:15 PM »
RELEASE: 13-096

NASA ADMINISTRATOR STATEMENT ON ALPHA MAGNETIC SPECTROMETER

WASHINGTON -- The following is a statement from NASA Administrator
Charles Bolden on the first Alpha Magnetic Spectrometer (AMS) results
announced Wednesday at the European Organization for Nuclear Research
(CERN) in Switzerland. AMS is a cosmic ray particle physics detector
on the exterior of the International Space Station. It was launched
to the space station on space shuttle Endeavour's STS-134 mission on
May 16, 2011.

"The AMS cosmic ray particle results announced today could help foster
a new understanding of the fields of fundamental physics and
astrophysics. I am confident that this is only the first of many
scientific discoveries enabled by the station that will change our
understanding of the universe. Multiple NASA human spaceflight
centers around the country played important roles in this work, and
we look forward to many more exciting results from AMS.

"For more than 50 years, NASA has pushed the boundaries beyond Earth
to unveil the underlying architecture of the cosmos, revealing new
knowledge about our place within it. The International Space Station
is a gateway to the universe, teaching us how humans can live, work,
and thrive in space as we endeavor to venture deeper into the solar
system. It's a remarkable testament that the orbital laboratory could
play such an important supporting role in research at the very
smallest scale of the physical universe. It's proof positive the
space station is humanity's greatest achievement in low-Earth orbit."


For more information about AMS and the International Space Station,
visit:

http://www.nasa.gov/station

Offline Targeteer

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #56 on: 04/03/2013 10:26 PM »
While hailing Endeavour, ISS, and AMS let's not forget to give some rare credit to the normally ineffectual US Congress which provided the money and specific direction to NASA to launch AMS which NASA had no plans (or capability) to do before the planned retirement of the shuttle.
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Offline IRobot

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #57 on: 04/03/2013 10:42 PM »
Jeez, the dark matter pseudo science continues!

Quote
Alternatively, the positrons could originate from pulsars, or what remains when a star collapses. Pulsars spew out charged particles as they whip around.

I just ask ONE question: if the search was for pulsars, was this evidence enough for their existence? Cause you can't have both!

Dear lord, I do believe we have a strong (> 5 sigma!) detection of a crank.

1) as to the pseudo science thing: Do you have another theory that explains both the CMB power spectrum, the BAO power spectrum, and the rotation curve of galaxies at the same time whilst being self-consistent and not requiring more than two parameters (in the case of CDM: density and temperature)? Didn't think so. (I know as a matter of fact that there are no such theories, so don't bother. Although do try, you might learn something.)

2)"Cause you can't have both!" You absolutely, positively can have both. Should have both, even, but with a different energy spectrum. This is coming from a pulsar astronomer.
1) VSL theory. And I know that is not well accepted.

2) I seriously doubt you are a pulsar astronomer after reading this:

http://www.symmetrymagazine.org/article/april-2013/ams-tiptoes-toward-answer-to-dark-matter-question

Quote
The AMS result, to be published in Physical Review Letters on April 5, includes data from the energy range between 0.5 and 350 GeV. A graph of the flux of positrons over the flux of electrons and positrons takes the shape of a valley, dipping in the energy range between 0.5 to 10 GeV and then increasing steadily between 10 and 250 GeV. After that point, it begins to dip again—but the graph cuts off just before one can tell whether this is the great drop-off expected in dark matter models or the gradual fade-out expected in pulsar models. This confirms previous results from the PAMELA experiment, with greater precision.

As you see, Pulsars have not been ruled out.

« Last Edit: 04/03/2013 10:45 PM by IRobot »

Offline Nomadd

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #58 on: 04/03/2013 11:06 PM »
 Did they ever say how much sensitivity at what energy levels they lost by ditching the cryo cooler? Maybe they're glad it didn't work, since they hope to get 18 years of data now instead of 3.

Offline Mr. D

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #59 on: 04/03/2013 11:12 PM »
Quote
1) VSL theory. And I know that is not well accepted.

While I am not a cosmologist (they're down the hall, doing cosmology fueled by their espresso machine that they refuse us access to!), you do realize that this is proposed as an alternative to inflation, which has precisely jack and crap to do with dark matter, and jack has just left the building. Indeed, the wiki page (hah!) has just one link to a dark matter "paper" which is on its own site... If you can't even get your theory peer-reviewed, it has some rather serious issues (even string theory manages that, even though it can't predict anything).

Quote
2) I seriously doubt you are a pulsar astronomer after reading this:
I seriously doubt you're a human being, then. Or something, says I, comfortably seated in my physics building all the while analysing pulsar data. Well, at home, but with ssh and all it makes no difference. Which, by definition, makes me a pulsar astronomer. Well, I'd rather be though of as an astrophysicist.

On the actual substance, though. You could reconcile the positron excess (which has been around for a while, by the way) with either some more Vela-like pulsars (or a bunch of old Velas, much more likely) or with DM annihilation, or, and this is important, with a linear combination thereof. The only thing that could rule out pulsars is if that excess had a fine line spectrum. A DM signal could be expected to be a fine line convolved with the kinetic energy distribution of the DM particles in the line of sight (which is what they're talking about in the second paragraph, the sharp drop being due to the exponential decay nature of thermal distributions) vs. power-law distributions for pulsar wind (although you could imagine some cutoff for the pulsar wind).

Quote
As you see, Pulsars have not been ruled out.
Where, oh where, was I claiming that? You seem to have reading comprehension issues.

I do not regret to say that this conversation is at an end unless you bring something vaguely resembling a valid point. (Something I wish I could say during EPO activities, but what with quality of service and all)

Edit: corrected a spelling mistake.
« Last Edit: 04/03/2013 11:13 PM by Mr. D »

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #60 on: 04/04/2013 08:02 AM »

Offline IRobot

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #61 on: 04/04/2013 11:13 AM »
A more critical look at the initial results: http://resonaances.blogspot.com/2013/04/first-results-of-ams-02.html
Thanks, that should put a cork on the pseudo pulsar astronomer.

I like this part:
Quote
There's absolutely no way that measurements of the  positron spectrum may give us a reliable evidence for dark matter: not now, and not anytime soon.

I also like this part although AFAIK there were some sun science made in Skylab...
Quote
The most important thing we learned today is that AMS works and exceeds in precision the previous instruments (which wasn't that obvious: it's the first time a serious experiment is performed on a space station, and besides the mission underwent a dramatic downgrade shortly before the launch).

Offline Chris Bergin

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #62 on: 04/04/2013 01:32 PM »
I've written an article about this, but mainly relating to the mission planning that enabled AMS-02 to actually get to the ISS:

http://www.nasaspaceflight.com/2013/04/endeavours-legacy-ams-02-proving-value/

Offline Space Pete

Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #63 on: 04/04/2013 03:45 PM »
it's the first time a serious experiment is performed on a space station

What the heck is this guy smoking? He's clearly another one of these "I know about science, and so despite the fact that I have done absolutely zero research on ISS science, that makes me qualified to speak about it authoritatively" type people.

Like we needed more of those.... ::)
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Offline arachnitect

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #64 on: 04/04/2013 05:04 PM »
Well, if nothing else, at least it's something we can point to and say: "This is something the ISS has done that we could not have done elsewhere!"

Didn't Jim say there's no reason AMS couldn't have flown as a free flyer if it had been planned from the start? Is ISS providing anything that a s/c bus couldn't?

While I'm glad AMS flew and ended up on ISS, it's easier to imagine a high-profile "big science" experiment like AMS getting it's own mission than many of the other hosted payloads that have gone to ISS, like SAGE-III or the Robotic Refueling Mission, not to mention things like nanoracks or the cubesats which have hitched rides on COTS/CRS flights.

Offline arkaska

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #65 on: 04/04/2013 06:46 PM »
it's the first time a serious experiment is performed on a space station

What the heck is this guy smoking? He's clearly another one of these "I know about science, and so despite the fact that I have done absolutely zero research on ISS science, that makes me qualified to speak about it authoritatively" type people.

Like we needed more of those.... ::)

One tip is to actually read the blog-post before you get all wind up ;)

"Résonaances is a particle physics blog from Paris. It's about the latest news and gossips in particle physics and astrophysics. The posts are often spiced with sarcasm, irony, and a sick sense of humor. The goal is to make you laugh; if it makes you think too, that's entirely on your own responsibility..."

http://resonaances.blogspot.se
« Last Edit: 04/04/2013 06:47 PM by arkaska »

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #66 on: 04/05/2013 09:45 AM »
it's the first time a serious experiment is performed on a space station

What the heck is this guy smoking? He's clearly another one of these "I know about science, and so despite the fact that I have done absolutely zero research on ISS science, that makes me qualified to speak about it authoritatively" type people.

Like we needed more of those.... ::)

One tip is to actually read the blog-post before you get all wind up ;)

"Résonaances is a particle physics blog from Paris. It's about the latest news and gossips in particle physics and astrophysics. The posts are often spiced with sarcasm, irony, and a sick sense of humor. The goal is to make you laugh; if it makes you think too, that's entirely on your own responsibility..."

http://resonaances.blogspot.se

Actually I don't think the remark should be controversial or even satyrical at all, if you read it in its proper context and not isolated. He's just remarking it's the first time a serious experiment [of this kind = particle physics!] is done on a space station (not just the ISS), which happens to be true. Other (major) physics experiments in space stations were either observational astrophysics or from other physics disciplines.
-DaviD-

Offline AnalogMan

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #67 on: 07/06/2013 01:41 AM »
Latest update:

New AMS results to be presented at ICRC 2013 at Rio de Janeiro, Brasil
July 5th, 2013
 
We are all looking forward  for  the planned release of several new results from the AMS Collaboration at the  International Cosmic Ray Conference 2013 in Brasil.
 
On July 8th, during a special ICRC  session dedicated to  AMS,  the  Collaboration will present new results on the precision measurement of:  proton, helium, electron, positrons and Boron/Carbon as well as the positron to electron ratio.
 
The data correspond to 24 month of data taking, about 31 billions of trigger recorded by the experiment and transferred to ground.
 
Stay tuned on this page for more news.
http://www.ams02.org/2013/07/new-ams-results-to-be-presented-at-icrc-2013-at-rio-de-janeiro-brasil/

Offline mlindner

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #68 on: 01/21/2014 11:04 AM »
Latest update:

New AMS results to be presented at ICRC 2013 at Rio de Janeiro, Brasil
July 5th, 2013
 
We are all looking forward  for  the planned release of several new results from the AMS Collaboration at the  International Cosmic Ray Conference 2013 in Brasil.
 
On July 8th, during a special ICRC  session dedicated to  AMS,  the  Collaboration will present new results on the precision measurement of:  proton, helium, electron, positrons and Boron/Carbon as well as the positron to electron ratio.
 
The data correspond to 24 month of data taking, about 31 billions of trigger recorded by the experiment and transferred to ground.
 
Stay tuned on this page for more news.
http://www.ams02.org/2013/07/new-ams-results-to-be-presented-at-icrc-2013-at-rio-de-janeiro-brasil/

So has there been any more information released?
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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #69 on: 01/21/2014 11:49 AM »
Yes, although there were basically no surprises with respect to the earlier releases. For now there is not enough sensitivity yet to differentiate dark matter models vs other standard explanations. No cutoff has been seen yet. I had the opportunity of attending several AMS-02 conference talks back in September, I can attach some slides from Marco Incagli.

Here, about the positron fraction and its consequences:
« Last Edit: 01/21/2014 11:56 AM by eeergo »
-DaviD-

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #70 on: 01/21/2014 11:57 AM »
Electron and positron fluxes.
-DaviD-

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #71 on: 01/21/2014 11:59 AM »
Proton and helium fluxes and B/C ratio + summary by W. Xu.
« Last Edit: 01/21/2014 12:02 PM by eeergo »
-DaviD-

Offline Prober

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #72 on: 01/23/2014 04:01 PM »
While hailing Endeavour, ISS, and AMS let's not forget to give some rare credit to the normally ineffectual US Congress which provided the money and specific direction to NASA to launch AMS which NASA had no plans (or capability) to do before the planned retirement of the shuttle.

Good point thanks for pointing this out.  We should give credit where credit is due.
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Offline AnalogMan

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #73 on: 07/04/2014 07:10 PM »
Came across this recent presentation given by Dr Samuel Ting:

"The Latest Results from The Alpha Magnetic Spectrometer on the International Space Station"
June 17, 2014
http://ams.nasa.gov/Documents/AMS_Publications/NASA%20JUNE-2014C.pdf
(50 slides, 6.8MB)

Not sure it has much that has not already been seen (its not a peer reviewed scientific paper).

Offline AnalogMan

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #74 on: 09/19/2014 04:32 PM »
Latest press release:

New results from the Alpha Magnetic Spectrometer on the International Space Station
September 18th, 2014

The new results on energetic cosmic ray electrons and positrons are announced today. They are based on the first 41 billion events measured with the Alpha Magnetic Spectrometer (AMS) on the International Space Station (ISS).  These results provide a deeper understanding of the nature of high energy cosmic rays and shed more light on the dark matter existence.
 
>Download AMS Collaboration Press Release
 
>Webcast of the seminar at CERN

>High Statistics Measurement of the Positron Fraction in Primary Cosmic Rays of 0.5–500 GeV with the Alpha Magnetic Spectrometer on the International Space Station

>Electron and Positron Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

AMS has analyzed 41 billion primary cosmic ray events.  Of these, 10 million have been identified as electrons and positrons.  AMS has measured the positron fraction (ratio of the number of positrons to the combined number of positrons and electrons) in the energy range 0.5 to 500 GeV.  We have observed that the energy at which the fraction starts to quickly increase is 8 GeV (see Figure 1) indicating the existence of a new source of positrons. Figure 2 shows that the exact rate at which the positron fraction increases with energy has now been accurately determined and the fraction shows no observable sharp structures.  The energy at which the positron fraction ceases to increase (corresponding to the turning point energy at which the positron fraction reaches its maximum) has been measured to be 275+32 GeV as shown in Figure 2 (upper plot). This is the first experimental observation of the positron fraction maximum after half a century of cosmic rays experiments. The excess of the positron fraction is isotropic within 3% strongly suggesting the energetic positrons may not be coming from a preferred direction in space.

[press release continues with lots more detail … ]
http://www.ams02.org/2014/09/new-results-from-the-alpha-magnetic-spectrometer-on-the-international-space-station/

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #76 on: 01/06/2017 04:51 PM »
Bump for 2016 release of 5 Year findings report and forward research plan:
LINK: http://www.ams02.org/2016/12/the-first-five-years-of-the-alpha-magnetic-spectrometer-on-the-international-space-station/


The First Five Years of the Alpha Magnetic Spectrometer on the International Space Station

December 8th, 2016

Unlocking the Secrets of the Cosmos: The First Five years of AMS on the International Space Station

>> Download the AMS Collaboration press release

The Alpha Magnetic Spectrometer (AMS) Collaboration announces the fifth anniversary of the AMS Experiment on the International Space Station (ISS) and summarizes its major scientific results to date.

The AMS Experiment (shown in Figure 1) is the most sensitive particle detector ever deployed in space and is exploring a new and exciting frontier in physics research. As a magnetic spectrometer, AMS is unique in physics research as it studies charged particles and nuclei in the cosmos before they are annihilated in the Earth’s atmosphere. The improvement in accuracy over previous measurements is made possible through its long duration time in space, large acceptance, built in redundant systems and its thorough calibration in the CERN test beam. These features enable AMS to analyze the data to an accuracy of ~1%. The first five years of data from AMS on the International Space Station are beginning to unlock the secrets of the cosmos.

Since its installation on the ISS in May 2011, AMS has collected data from more than 90 billion cosmic rays with up to multi-TeV energies and published its major physics results in Physical Review Letters.

A note about cosmic rays: As the products of exploding supernovae, primary cosmic rays can travel for millions of years in the galaxy before reaching AMS. Secondary cosmic rays come from the interaction of primary cosmic rays with the interstellar media. Uniquely positioned on the International Space Station, AMS studies cosmic rays passing through its precision detectors, to define the charge, energy, and momentum of the passing particles in order to obtain an understanding of dark matter, the existence of complex antimatter in space, the properties of primary and secondary cosmic rays as well as new, unexpected phenomena. These are among the fundamental issues in modern physics.

There are hundreds of different kinds of charged elementary particles.   Only four of them – electrons, protons, positrons and antiprotons – have infinite lifetimes so they can travel through the cosmos forever. Electrons and positrons have much smaller mass than protons and antiprotons so they lose much more energy in the galactic magnetic field due to synchrotron radiation.

As shown in Figure 2, AMS has observed that the electron flux and positron flux display different behaviors both in their magnitude and in their energy dependence.

Most surprisingly, from 60 to 500 GeV, positrons, protons and antiprotons display identical momentum dependence but electrons exhibit a totally different dependence as shown in Figure 3. The reason that this observation is surprising is that both electrons and positrons lose energy (or momentum) equally when travelling through the galactic magnetic field and at a much higher rate than protons or antiprotons.

There has been much interest over the last few decades in understanding the origin and nature of dark matter. When particles of dark matter collide, they produce energy that transforms into ordinary particles, such as positrons and antiprotons. The characteristic signature of dark matter is an increase with energy followed by a sharp drop off at the mass of dark matter as well as an isotropic distribution of the arrival directions of the excess positrons and antiprotons.

Figure 4 shows the latest results from AMS on the positron flux. As seen from the figure, after rising from 8 GeV above the rate expected from cosmic ray collisions, the spectrum exhibits a sharp drop off at high energies in excellent agreement with the dark matter model predictions with a mass of ~1 TeV. There is great interest in the physics community on the AMS measurements of elementary particles. For example, an alternative speculation for positron spectrum is that this rise and drop off may come from new astrophysical phenomena such as pulsars.

AMS has also studied the antiproton to proton ratio. The excess in antiprotons observed by AMS cannot easily be explained as coming from pulsars but can be explained by dark matter collisions or by other new astrophysics models. Antiprotons are very rare in the cosmos. There is only one antiproton in 10,000 protons therefore a precision experiment requires a background rejection close to 1 in a million. It has taken AMS five years of operations to obtain a clean sample of 349,000 antiprotons. Of these, AMS has identified 2200 antiprotons with energies above 100 billion electron volts. Experimental data on cosmic ray antiprotons are crucial for understanding the origin of antiprotons in the cosmos and for providing insight into new physics phenomena.

Protons are the most abundant particles in cosmic rays. AMS has measured the proton flux to an accuracy of 1% with 300 million protons and found that the proton flux cannot be described by a single power law, as had been assumed for decades, and that the proton spectral index changes with momentum.

AMS contains seven instruments with which to independently identify different elementary particles as well as nuclei. Helium, lithium, carbon, oxygen and heavier nuclei up to iron have been studied by AMS. It is believed that helium, carbon and oxygen were produced directly from primary sources in supernova remnants whereas lithium, beryllium and boron are believed to be produced from the collision of primary cosmic rays with the interstellar medium. Primary cosmic rays carry information about their original spectra and propagation, and secondary cosmic rays carry information about the propagation of primary and secondary cosmic rays and the interstellar medium.

Helium is the second most abundant cosmic ray. Helium has been studied over the past century. Although lithium is a secondary cosmic ray, its spectrum behaves similarly to protons and helium in that none of the three fluxes can be described by a single power law and they do change their behavior at the same energy.

Since protons, helium, carbon and oxygen are primary cosmic rays and produced at the same sources; thus their flux ratios should be rigidity independent. Rigidity is momentum per unit charge and is the metric by which magnetic fields, such as those experienced by cosmic rays between their origin and AMS, act on charged particles. From the AMS measurements, for carbon-to-helium and for carbon-to-oxygen these ratios are, indeed, independent of rigidity, i.e., flat, as expected. Unexpectedly, the proton-to-helium flux ratio drops quickly but smoothly with rigidity.

Other secondary cosmic rays being measured by AMS include boron and beryllium. The unstable isotope of beryllium, 10Be, has a half-life of 1.5 million years and decays into boron. The Be/B ratio therefore increases with energy due to time dilation when the Be approaches the speed of light. Hence, the ratio of beryllium to boron provides information on the age of the cosmic rays in the galaxy. From this, AMS has determined that the age of cosmic rays in the galaxy is ~12 million years.

The flux ratio between secondary cosmic rays (boron) and primary cosmic rays (carbon) provides information on propagation and the average amount of interstellar material (ISM) through which the cosmic rays travel in the galaxy. Cosmic ray propagation is commonly modeled as a fast moving gas diffusing through a magnetized plasma. Various models of the magnetized plasma predict different behavior of the boron-to-carbon (B/C) flux ratio. Remarkably, above 65 GeV, the B/C ratio measured by AMS is well described by a single power law B/C= kRd with d = -0.333±0.015. This is in agreement with the Kolmogorov turbulence model of magnetized plasma where d = -1/3 asymptotically. Of equal importance, the B/C ratio does not show any significant structures in contrast to many cosmic ray models.

The carbon and oxygen fluxes, which are both primary cosmic rays, and the boron, lithium, and beryllium fluxes, which are secondary, have characteristically different rigidity dependences.

The Big Bang origin of the Universe requires that matter and antimatter be equally abundant at the very hot beginning of the universe. The search for the explanation for the absence of antimatter in a complex form is known as Baryogenesis. Baryogenesis requires both a strong symmetry breaking and a finite proton lifetime. Despite the outstanding experimental efforts over many years, no evidence of strong symmetry breaking nor of proton decay have been found. Therefore, the observation of a single anti-helium event in cosmic rays is of great importance.

In five years, AMS has collected 3.7 billion helium events (charge Z = +2). To date we have observed a few Z = -2 events with mass around 3He. At a rate of approximately one antihelium candidate per year and a required signal (antihelium candidates) to background (helium) rejection of one in a billion, a detailed understanding of the instrument is required. In the coming years, with more data, one of our main efforts is to ascertain the origin of the Z = -2 events.

In five years, AMS on the ISS has recorded more than 90 billion cosmic ray events. The latest AMS measurements of the positron spectrum and positron fraction, the antiproton/proton ratio, the behavior of the fluxes of electrons, positrons, protons, helium and other nuclei provide precise and unexpected information on the production, acceleration and propagation of cosmic rays. The accuracy and characteristics of the data, simultaneously from many different types of cosmic rays require the development of a comprehensive model. In the coming years, with more data, one of our main efforts is to ascertain the origin of the Z = -2 events.

Most importantly, AMS will continue to collect and analyze data for the lifetime of the Space Station. As the results to date have demonstrated, whenever a precision instrument such as AMS is used to explore the unknown, new and exciting discoveries can be expected.

The results of the first five year have been presented on December the 8th, 2016, at 17:00 (Geneva time) in a CERN Colloquium:

https://indico.cern.ch/event/592392/

------------------------------------------

Captions for figures in order of the Summary of the latest findings report:
Figure 1. From its vantage point ~240 miles (400 km) above the Earth, the Alpha Magnetic Spectrometer (AMS) collects data from passing cosmic rays from primordial sources in the universe before they pass through the Earth’s atmosphere.

Figure 2. The electron flux and the positron flux are different in their magnitude and energy dependence.

Figure 3. The positron, proton, and antiproton spectra have identical momentum dependence from 60 to 500 GeV. The electron spectrum exhibits a totally different behavior, it decreases much more rapidly with increasing momentum.

Figure 4. The current AMS positron flux measurement compared with theoretical models.
« Last Edit: 01/06/2017 04:54 PM by russianhalo117 »

Offline catdlr

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #77 on: 10/14/2017 02:35 AM »
October 13, 2017
MEDIA ADVISORY M17-117

NASA Johnson Space Center Invites Media to Screening of Documentary on Alpha Magnetic Spectrometer
Media are invited to attend the screening of “AMS: The Fight for Flight,” a NASA documentary about the Alpha Magnetic Spectrometer (AMS) and its principal investigator, Nobel laureate Samuel Ting.

The one-hour historical documentary, to be shown at 6 p.m. Oct. 17 at Space Center Houston, showcases the capabilities of the International Space Station as a science platform. It follows the development of the Alpha Magnetic Spectrometer, a science instrument studying the fundamental nature of the universe, through Ting’s efforts. The story focuses on the dedication of Ting, former NASA officials and Congress to fly it to the station on the next to last space shuttle mission.

The audience will include Johnson Space Center employees and special invited guests. Media planning to attend must contact the Johnson Space Center newsroom at 281-483-5111 no later than 5 p.m. Oct. 16.

International Space Station Program Manager Kirk Shireman will welcome attendees and Ting will provide a short presentation. Media will be able to conduct individual interviews after the event.

Originally proposed in 1994 by Ting, an MIT professor of Physics, the AMS was built by over 600 physicists and engineers all over the world. One of the most complex physics experiments ever launched into space, the AMS searches for evidence of dark matter and antimatter in the universe. It’s history spans 23 years from the drawing table to its final home on the space station.

    
Press Contacts

Gary Jordan
Johnson Space Center, Houston
281-483-5111
[email protected]

    
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Tony De La Rosa

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #78 on: 11/21/2017 12:20 PM »
Interesting set of (contradictory) papers on the main result by AMS-02:

http://science.sciencemag.org/content/358/6365/911

https://journals.aps.org/prd/abstract/10.1103/PhysRevD.96.103013

The HAWC Earth-based Cherenkov telescopes have performed precision measurements of TeV-scale gamma flux from pulsars, correlated with positron flux. The first paper concludes pulsars are insufficient to explain the AMS-02/PAMELA/CALET (and, in the near future, one would expect ISS-CREAM) positron excess observed, strengthening the need to invoke a more exotic solution to the excess (dark matter, but also others).

However :) the second paper, with the same data, does just the contrary: for them, the excess is compatible with the larger high-energy gamma flux measured.

So I'd say the conclusion for now is that the jury is still out!
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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #79 on: 05/03/2018 12:29 AM »
"AMS looks at Galactic Cosmic Rays" - CERN/EP Newsletters - by Panos Charito

Quote
Highly energetic particles consist of essentially every element ranging from hydrogen, accounting for approximately 89% of the GCR spectrum. The idea that Supernova Remnant (SNR) shocks are the primary sites of CR acceleration in the Galaxy is what is generally referred to as the ”Supernova remnant paradigm for the origin of Cosmic Rays”. This paradigm has been under scrutiny now for about 50 years, but only in the last few years some clear evidence in its favour has been found. [...]

AMS provides a continuous stream of time-resolved and multichannel Cosmic Ray data that set new objectives, namely: (i) to advance solar modulation observations of Cosmic Ray particles and antiparticles, and (ii) to develop improved and measurement-validated models of Cosmic Ray transport in the heliosphere.

Moreover, the new data allow to understand the puzzling anomalies detected in the energy spectra of CR proton and helium nuclei while also maintaining the universality of the dominant diffusive-shock acceleration mechanism.  In this model, the p/He anomaly is explained by a flux transition between two source components that have different injection spectra and composition.

Another important topic is the recent observation of an eight-month time lag in solar modulation of Cosmic Rays. This effect reveals important properties on the dynamics of the formation and changing conditions of the heliospheric plasma. Crucial tests can be performed by AMS via monthly-resolved measurements of these ratios, or even better, by measurements of individual particle fluxes for protons, antiprotons, electrons and positrons under both polarity conditions and across the magnetic reversal. This demonstrates that time-dependent measurements on CR antimatter can provide precious information on the physics of the heliosphere. Finally, understanding the charge-sign dependence of Cosmic Ray modulation is also essential to search for dark matter signatures in Cosmic Ray fluxes.

https://ep-news.web.cern.ch/content/ams-looks-cosmic-galactic-rays
« Last Edit: 05/03/2018 12:29 AM by eeergo »
-DaviD-

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Re: AMS-2 (Alpha Magnetic Spectrometer)
« Reply #80 on: 06/19/2018 08:26 PM »
NASA's "AMS: The Fight for Flight" documentary is now available.

Streaming right now on Google Play and Amazon Video.
https://play.google.com/store/movies/details/NASA_Presents_AMS_The_Fight_for_Flight?id=Zy4c-mIlcNY
https://www.amazon.com/dp/B07D7PZW7R/ref=nodl_

Learn about the Alpha Magnetic Spectrometer (AMS), a particle physics experiment on the International Space Station, the history of this revolutionary experiment and the man behind it.

Originally proposed in 1994 by Samuel Ting, a Nobel laureate and MIT Professor of Physics, and built by over 600 physicists and engineers all over the world, the Alpha Magnetic Spectrometer is by far the most complex physics experiment ever launched into space. The goal of the instrument is to help researchers unlock the mysteries of antimatter and better understand the structure of our universe.

While still under construction, the AMS experiment suffered a major setback because of the Space Shuttle Columbia tragedy in 2003. Soon after, the decision was made to cancel the space shuttle program, and as a result the AMS was removed from the manifest. After ten years and $1.5B spent, there would be no ride to the space station.

This film tracks the AMS's 23 year journey from the drawing board to its final home on the space station. Along the way, we look back at the adversity that principal investigator Sam Ting was forced to overcome with the help of NASA and key members of Congress. Ultimately, it's a story of one man's remarkable tenacity and that of different branches of government working with researchers in order to produce great science for the benefit of all humankind.

Interviews include:
Dan Goldin
Michael Griffin
Bill Nelson
Kay Bailey Hutchinson

Narrated by George Takei

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