Author Topic: Russian RadioAstron (Spectr-R) update  (Read 49270 times)

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #60 on: 12/21/2016 04:16 PM »
http://www.asc.rssi.ru/radioastron/ao-5/ao5.html
RadioAstron Announcement of Opportunity - 5

 The space VLBI Mission RadioAstron, led by the Astro Space Center (ASC) of Lebedev Physical Institute, provides a range of specific and unique capabilities for detecting and imaging sources of cosmic radio emission at the highest angular resolution. The optimal utilization of these capabilities relies on the construction and execution of a balanced scientific program for the Mission. Proposals are invited for the RadioAstron Key Science Program and General Observing Time experiments to be submitted by 23 January 2017, 23:59 UT, to the Mission, and to ground radio telescopes required for the specific observations by their respective proposal deadlines. AO-5 observations will be performed between July 2017 and June 2018 inclusive.
 Proposals are to be submitted by e-mail as single pdf files to the address: [email protected]

 List of AO-5 related documents

- The RadioAstron Announcement of Opportunity - 5;
- The RadioAstron User Handbook;
- Full Proposal template: LaTeX file and pdf file;
- All-sky uv-coverage simulations with Pushchino and Green Bank tracking stations: pdf file;
- ASCII table with RadioAstron AO-5 visibility prediction for selected targets from the RadioAstron list of observed sources;
- Fakerat full binary package (is tested to work with most Linux distributions) including installation README, manual, and predicted RadioAstron AO5 orbit prior to the maneuver planned for 2017-07-16 and after it (ASCII files);
- All documents collected togeter in a zip-file
- RadioAstron observations status summary. Acknowledgment for the project publications

 To subscribe to RadioAstron Newsletter click here
« Last Edit: 12/21/2016 04:34 PM by Salo »

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #61 on: 03/15/2017 04:09 PM »
http://www.asc.rssi.ru/radioastron/news/newsl/en/newsl_31_en.pdf
======================
Astro Space Center
RadioAstron Newsletter
Number 31
15 March 2017
======================

The RadioAstron AO-5 open science program: July 2017 – June 2018

The  RadioAstron  observations  currently  cover  the  fourth  year  of  the  open  program  within  the approved AO-4 proposals.  Starting from July 2017, the RadioAstron mission will move into the fifth year of its program, AO-5 observations will continue until June 2018.  We note that an orbit correction is planned for July 2017 which will affect the RadioAstron observing schedule in July and  August  2017.   The  fifth  RadioAstron  Announcement  of  Opportunity  has  invited  proposals of the following two types:  the “Key Science Program” (KSP) and “General Observing Time” (GOT).  See  for  details  the  full  set  of  announcement  documents  in http://www.asc.rssi.ru/radioastron/ao-5/ao5.html .
All proposal were evaluated by the RadioAstron Program Evaluation Committee (RPEC) which was appointed by the RadioAstron International Science Council (RISC). Results of the evaluation were approved by the RadioAstron project director Nikolai Kardashev.  RPEC members for AO-5 are Jason Hessels (U. Amsterdam, the Netherlands), David Jauncey (CSIRO, Australia), Matthew Lister (Purdue U., USA), Alexander Pushkarev (CrAO, Russia), Mark Reid (chair, Harvard CfA, USA), Olaf Wucknitz (MPIfR, Germany). Below we list 11 accepted projects which have requested observations with RadioAstron during the AO-5 period in their submission order:

• GOT: “Visibility tracking of hyper-compact H2O maser spots for studying interstellar microturbulence”, PIs:  Hiroshi Imai (Kagoshima U., Japan), Alexey Alakoz (ASC Lebedev, Russia);
• GOT: “Monitoring of substructure in scattering disk of pulsar radio emission”, PI: Carl Gwinn (UCSB, USA);
• GOT: “Brightest objects in the distant Universe”, PI: Leonid Gurvits (JIVE and TU Delft, the Netherlands);
• KSP: “Evolution of high brightness temperature AGN cores with RadioAstron”, PI: Yuri Kovalev (ASC Lebedev, Russia);
• KSP:  “Probing  the  innermost  regions  of  AGN  jets  and  their  magnetic  fields”,  PI:  Jose-Luis Gomez (IAA, Spain);
• GOT: “Probing interstellar scattering material using dense RadioAstron observations of refractive substructure in AGN”, PI: Mikhail Lisakov (ASC Lebedev, Russia);
• GOT: “Observations of the central maser regions in H2O megamaser NGC4258 with ultimate angular resolution”, PI: Willem Baan (ASTRON, the Netherlans).
• GOT: “Early stages of massive star formation regions as seen with RadioAstron in H2O maser lines”, PI: Stan Kurtz (UNAM, Mexico);
• KSP: “Gravitational redshift experiment with RadioAstron”, PI: Valentin Rudenko (SAI MSU, Russia);
• KSP:  “The  nuclear  structure  in  M87  with  RadioAstron”,  PI:  Tuomas  Savolainen  (Aalto  U., Finland; MPIfR, Germany);
• GOT: “Resolving the gamma-ray production region in sources J0211+1051 and S5 1044+71”, PI: Victor Patino-Alvares (MPIfR, Germany).

Among the approved projects, six got rank ‘A’ (the highest priority).  A total of more than 160 co-investigators represent 20 countries.  The largest number of co-Is are from Russia, other countries with a high number of co-investigators include the USA, Germany, Spain, the Netherlands, Australia, Canada.

The absolute record of angular resolution by RadioAstron. Again.

While the readers are welcome to enjoy recent RadioAstron publications
( http://www.asc.rssi.ru/radioastron/publications/publ.html ), we are happy to announce a new absolute record of the angular resolution which was achieved detecting the megamaser in NGC 4258 at 1.3 cm on the
RadioAstron Space Radio Telescope to Medicina (Italy) baseline of 340,000 kilometers (26.7 Earth diameters,  8 μas).  The previous record of 11 μas on the same megamaser by the RadioAstron SRT to the GBT baseline was announced during the EVN symposium in Sankt-Petersburg.
In the same time, within a dedicated experiment on the glorious pair of the quasars 3C 273 and 3C 279, a very compact core was detected in 3C 279 at 1.3 cm by the SRT to the Jansky VLA baseline of 235,000 kilometers (18.5 Earth diameters, 12 μas).
These results are crucial to probe the physics of both the water vapor megamasers and the extremely bright and compact cores of quasars.

Nikolai Kardashev ([email protected])
Yuri Kovalev ([email protected])

Offline Olaf

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Re: Russian RadioAstron (Spectr-R) update
« Reply #62 on: 07/16/2017 03:10 PM »
https://www.roscosmos.ru/23770/
bing translation
On 16 July, in 9:00, the Lavochkin NGO PCO made a correction to the orbit of the spectrum-R spacecraft, provided to prevent the spacecraft from being hit in January 2018 by a long (4.5 hour) solar shadow of the earth and extending the ballistic existence of spacecraft at least until the end of 2019.

The highly elliptical orbit of the spectrum-R is characterized by a significant evolution of parameters through the influence of the moon, is the so-called "evolving" orbit, which, on the one hand, enhances the possibilities of scientific observation, on the other, requires careful monitoring and prediction of its behaviour.

A similar correction was made successfully in March 2012. Due to the long interruption in the use of the adjustment engines one month prior to the nominal adjustment, on 16 June, a test correction was carried out by Lavochkin NGO specialists to confirm that the major correction engines worked in the staff and there was no need to use reserve engines. The impulse of the trial correction was less than at the nominal rate when engine time was 290.3 seconds.

A feature of the spacecraft correction was that they were carried out without interruption of the scientific program. The test adjustment practically did not change the orbit of the spacecraft, and the results of the nominal correction were previously taken into account by scientists in the establishment of the open scientific programme of the Space Astrophysical Observatory for the Spectrum-R for 2017-2018 years.

The Spectrum-R spacecraft has been developed in the NGO Lavochkin and is the space component of the international project of Astronomy. The project is implemented by the Astro Space Physical Institute Centre. P.N. Lebedev of the Russian Academy of Sciences, together with other institutions of the wounds and organizations of the State Corporation for space activities.

The purpose of the project is to carry out basic astrophysical research in the electromagnetic spectrum. Observations are made through terrestrial radio telescopes (more than 40) and the Spectrum-R Orbital Observatory. Together they form a radio interferometer with a, base, which allows you to get images of distant objects in the universe with an unparalleled angular resolution fixed at 8 microseconds of the arc.

The Spectrum-R spacecraft and the design of the radio telescope have been developed by Lavochkin NGOs. A unique telescope antenna with a diameter of 10 meters is made of composite material and consists of 27 drop blades and a central mirror of 3 meters. The apparatus is the largest space radio telescope in the world!


           

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #63 on: 11/20/2017 04:27 PM »
http://www.asc.rssi.ru/radioastron/news/newsl/en/newsl_32_en.pdf
======================
Astro Space Center
RadioAstron Newsletter
Number 32
27 July 2017
======================

Successful Spektr-R orbit correction

The planned orbit correction of the Spektr-R space craft was successfully performed by the Lavochkin Association on 16 July 2017 at 06:00 UT. The total impulse was equal to 1.6 m/s, accuracy 2 %.  As a result, the corrected orbit is very close to its predicted values.  The correction was made in order to avoid an excessively long shadow and a too low perigee in the first half of 2018.  The planned science program continues to the full extent. We congratulate colleagues with the 6th anniversary of the launch!

Nikolai Kardashev ([email protected])
Yuri Kovalev ([email protected])

The RadioAstron project is led by the Astro Space Center of the Lebedev Physical Institute of the Russian Academy of Sciences and the Lavochkin Scientific and Production Association under a contract with the Russian Federal Space Agency, in collaboration with partner organizations in Russia and other countries.

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #64 on: 11/20/2017 04:38 PM »
http://www.asc.rssi.ru/radioastron/news/newsl/en/newsl_33_en.pdf
======================
Astro Space Center
RadioAstron Newsletter
Number 33
20 November 2017
======================

RadioAstron has switched to a backup synchronization mode

The hydrogen maser onboard the RadioAstron space Radio Telescope has finished its operations in July 2017 after six years of perfect performance, due to the exhaustion of its neutral hydrogen. This was consistent with its expected lifetime.
The RadioAstron science and technical operations working group has performed a number of checks  of  two  other  methods  of  synchronization:  one  utilizing  the  onboard  rubidium  standard, and  the  other  being  the  so-called  closed–loop  mode  of  operations.   The  latter  uses  the  ground atomic clock located in Pushchino (Russia) or Green Bank (USA) tracking station.  Both modes have  successfully  delivered  interferometric  fringes.   At  the  same  time,  best  results  are  achieved with the closed–loop mode, as expected.  This mode of synchronization is being used right now as the default for observations in the AO5 science program.
RadioAstron AO6 proposals will be due by January 22, 2018 for observations from July 2018 – June 2019.  An announcement of the proposal call will be made in the near future.

Testing Einstein’s general relativity

The RadioAstron Key Science Program on the gravitational redshift experiment has completed its data collection stage. The observations for the experiment were supported by EVN, NRAO, and several geodetic radio telescopes (Badary-Russia, Effelsberg-Germany, GBT-USA, Hartebeesthoek-South Africa, Onsala-Sweden, Svetloe-Russia, VLBA-USA, Wettzell-Germany, Yarragadee-Australia, Yebes-Spain,  Zelenchukskaya-Russia).  The goal of the project is to test Einstein’s Equivalence Principle  — the  basis  of  general  relativity.  Specifically,  the  team aims  to  verify  Einstein’s  formula for the gravitational redshift effect or, equivalently, the gravitational time dilation due to a nearby massive body.  For the RadioAstron spacecraft the effect due to the Earth is about − 58 microseconds per day relative to an observer at the Earth’s surface — time actually flows faster
aboard  the  spacecraft  hence  the  minus  sign. The  most accurate test of this kind to date was performed  in  1976  by  the  NASA-SAO  Gravity  Probe  A  mission.   That  experiment  proved  the validity of Einstein’s formula with an accuracy of about 0.01 % using a suborbital probe equipped with  a  hydrogen  maser  frequency  standard.   The  experiment  with  RadioAstron  is  based  on  a similar approach, depicted in Figure 1, but benefitted from a better performing hydrogen maser and  a favorable  highly  eccentric  orbit,  which  allowed  the  team  to  perform  their  measurements team believe they’ll be able to supersede the result of their renowned predecessor by an order of magnitude.  This anticipated result will mark an important milestone in our challenge to find the level at which general relativity breaks down and a more general theory, such as string theory, is beginning to reveal its subtle features.  The team have recently published a paper (Litvinov et al. https://doi.org/10.1016/j.physleta.2017.09.014 ), presenting their techniques and giving a status update of the experiment.  Figure 2 illustrates the results of preliminary data processing of one of the experiments.  While the data processing is far from finished, the currently achieved accuracy is already at the level of that of Gravity Probe A.

Nikolai Kardashev ([email protected])
Yuri Kovalev ([email protected])

The RadioAstron project is led by the Astro Space Center of the Lebedev Physical Institute of the Russian Academy of Sciences and the Lavochkin Scientific and Production Association under a contract with the Russian Federal Space Agency, in collaboration with partner organizations in Russia and other countries.

To subscribe or un-subscribe to the Newsletter, use: http://asc-lebedev.ru/index2.php?engdep=22


Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #65 on: 11/20/2017 04:57 PM »
http://www.sciencedirect.com/science/article/pii/S0375960117304553?via%3Dihub
Probing the gravitational redshift with an Earth-orbiting satellite
Author links open overlay panel D.A.Litvinov V. N.Rudenko A.V.Alakoz U.Bach N.Bartele A.V.Belonenko K.G.Belousov M.Bietenholze A.V.Biriukov R.Carmang G.Cimóh C.Courde D.Dirkx D.A.Duev A.I.Filetkin G.Granato L.I.Gurvitsh A.V.Gusev …M.V.Zakhvatkin
https://doi.org/10.1016/j.physleta.2017.09.014
Get rights and content

Abstract

We present an approach to testing the gravitational redshift effect using the RadioAstron satellite. The experiment is based on a modification of the Gravity Probe A scheme of nonrelativistic Doppler compensation and benefits from the highly eccentric orbit and ultra-stable atomic hydrogen maser frequency standard of the RadioAstron satellite. Using the presented techniques we expect to reach an accuracy of the gravitational redshift test of order 10-5, a magnitude better than that of Gravity Probe A. Data processing is ongoing, our preliminary results agree with the validity of the Einstein Equivalence Principle.
« Last Edit: 11/20/2017 05:02 PM by Salo »

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #66 on: 12/22/2017 03:57 PM »
http://www.asc.rssi.ru/radioastron/ao-6/ao6.html
RadioAstron Announcement of Opportunity - 6

 The space VLBI Mission RadioAstron, led by the Astro Space Center (ASC) of Lebedev Physical Institute, provides a range of specific and unique capabilities for detecting and imaging sources of cosmic radio emission at the highest angular resolution. The optimal utilization of these capabilities relies on the construction and execution of a balanced scientific program for the Mission. Proposals are invited for the RadioAstron Key Science Program and General Observing Time experiments to be submitted by 22 January 2018, 23:59 UT, to the Mission, and to ground radio telescopes required for the specific observations by their respective proposal deadlines. AO-6 observations will be performed between July 2018 and June 2019 inclusive.
 Proposals are to be submitted by e-mail as single pdf files to the address: [email protected]

 List of AO-6 related documents
- The RadioAstron Announcement of Opportunity - 6;
- The RadioAstron User Handbook;
- Full Proposal template: LaTeX file and pdf file;
- All-sky uv-coverage simulations with Pushchino and Green Bank tracking stations: pdf file;
- ASCII table with RadioAstron AO-6 visibility prediction for selected targets from the RadioAstron list of observed sources, its visual representation can be found here;
- Fakerat full binary package (is tested to work with most Linux distributions) including installation README, manual, and predicted RadioAstron orbit for AO6;
- RadioAstron observations status summary;
- All documents collected together in a zip-file.  Also see acknowledgments for RadioAstron publications.
« Last Edit: 12/22/2017 04:07 PM by Salo »

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #67 on: 03/27/2018 02:49 PM »
http://iopscience.iop.org/article/10.3847/1538-4357/aab096
Quote
The Astrophysical Journal

Sun-sized Water Vapor Masers in Cepheus A

A. M. Sobolev1, J. M. Moran2, M. D. Gray3, A. Alakoz4, H. Imai5, W. A. Baan6, A. M. Tolmachev4, V. A. Samodurov4,7, and D. A. Ladeyshchikov1

Published 2018 March 26 • © 2018. The American Astronomical Society. All rights reserved.
The Astrophysical Journal, Volume 856, Number 1

Article information
Abstract

We present the first VLBI observations of a Galactic water maser (in Cepheus A) made with a very long baseline interferometric array involving the RadioAstron Earth-orbiting satellite station as one of its elements. We detected two distinct components at −16.9 and 0.6 km s−1 with a fringe spacing of 66 μas. In total power, the 0.6 km s−1 component appears to be a single Gaussian component of strength 580 Jy and width of 0.7 km s−1. Single-telescope monitoring showed that its lifetime was only eight months. The absence of a Zeeman pattern implies the longitudinal magnetic field component is weaker than 120 mG. The space–Earth cross power spectrum shows two unresolved components smaller than 15 μas, corresponding to a linear scale of 1.6 × 1011 cm, about the diameter of the Sun, for a distance of 700 pc, separated by 0.54 km s−1 in velocity and by 160 ± 35 μas in angle. This is the smallest angular structure ever observed in a Galactic maser. The brightness temperatures are greater than 2 × 1014 K, and the line widths are 0.5 km s−1. Most of the flux (about 87%) is contained in a halo of angular size of 400 ± 150 μas. This structure is associated with the compact H ii region HW3diii. We have probably picked up the most prominent peaks in the angular size range of our interferometer. We discuss three dynamical models: (1) Keplerian motion around a central object, (2) two chance overlapping clouds, and (3) vortices caused by flow around an obstacle (i.e., von Kármán vortex street) with a Strouhal number of about 0.3.

Offline Salo

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Re: Russian RadioAstron (Spectr-R) update
« Reply #68 on: 04/07/2018 03:33 AM »
http://www.asc.rssi.ru/radioastron/news/newsl/en/newsl_34_en.pdf
======================
Astro Space Center
RadioAstron Newsletter
Number 34
5 April 2018
======================

The RadioAstron AO-6 open science program: July 2018 { June 2019

The RadioAstron observations currently cover the fth year of the open program within the approved AO-5 proposals. Starting from July 2018, the RadioAstron mission will move into the sixth year of its program, AO-6 observations will continue until June 2019. The sixth RadioAstron Announcement of Opportunity has invited proposals of the following two types: the \Key Science Program" (KSP) and \General Observing Time" (GOT). See for details the full set of announcement documents in http://www.asc.rssi.ru/radioastron/ao-6/ao6.html.
All proposal were evaluated by the RadioAstron Program Evaluation Committee (RPEC) which was appointed by the RadioAstron International Science Council (RISC). Results of the evaluation were approved by the RadioAstron project director Nikolai Kardashev. RPEC members for AO-6 are Matthew Lister (chairman, Purdue U., USA), David Jauncey (CSIRO, Australia), Alexander Pushkarev (CrAO, Russia), Olaf Wucknitz (MPIfR, Germany), Benito Marcote (JIVE, the Netherlands), and Liz Humphreys (ESO).
Below we list 13 accepted projects which have requested observations with RadioAstron during the AO-6 period in their submission order:
• GOT: \Visibility tracking of hyper-compact H2O maser spots for studying interstellar microturbulence", PI: Hiroshi Imai (Kagoshima Uni., Japan);
• KSP: \Monitoring of substructure in scattering disks of pulsar radio emission", PI: Carl Gwinn (UCSB, USA);
• GOT: \Two-dimensional mapping of the interstellar scattering screen for Crab pulsar", PI: Robert Main (CITA, Canada);
• GOT: \Episodic accretion and ejection in massive star formation as seen with RadioAstron in 22 GHz H2O maser line", PI: Olga Bayandina (ASC, Russia);
• GOT: \High angular resolution observations of bright \water fountains" and H2O stellar masers", PI: Mikhail Shchurov (ASC, Russia);
• GOT: \The peculiar AGN PKS 0521-365 under the space-VLBI lupe", PI: Eduardo Ros (MPIfR, Germany; Uni.Valencia, Spain);
• KSP: \Probing interstellar scattering with dense RadioAstron observations of refractive substructure in AGN", PI: Mikhail Lisakov (ASC, Russia);
• KSP: \A twenty-fold zoom into the structure of the bright enigmatic blazar AO0235+164", PI: Leonid Gurvits (JIVE, Netherlands; TU Delft, Netherlands);
• GOT: \Measuring the Angular Sizes of the High-Velocity Components in the Megamaser NGC4258", PI: James Moran (CfA, USA);
• GOT: \Zooming into the jet launching region of the radio galaxy Cygnus A", PI: Uwe Bach (MPIfR, Germany);
• KSP: \Probing the innermost regions of AGN jets and their magnetic elds", PI: Jose L. Gomez (IAA, Spain);
• GOT: \Multi-frequency synthesis of active galactic nuclei at 22 GHz", PI: Victor Zuga (ASC, Russia);
• GOT: \N113 { extraordinary water maser in star forming region in the Large Magellanic Cloud", PI: Andrej Sobolev (UFSU, Russia).
Among the approved projects, four got rank `A' (the highest priority), seven | rank `B', and two | rank `C'. A total of 150 co-investigators represent 20 countries. The largest number of co-Is are from Russia, other countries with a high number of co-investigators include Germany, Spain, USA, Australia, and Canada.

Sun-sized water vapour maser spots in Cepheus A

RadioAstron detected the water maser emission at 22 GHz from Cepheus A on a baseline longer than 3 Earth diameters. This one of the nearest high-mass star-forming region, located at a distance of 700 pc. Further data processing reveals two distinct maser components at -16.9 and 0.6 km/s with an angular resolution of 66 μas. Their morphology is shown in Fig. 1. In relatively short ground baselines, the 0.6 km/s component appears in cross power spectrum as a single Gaussian. The space-ground spectrum shows two spectral features separated in velocity. They contain about 13% of the total ux density. This corresponds to two unresolved spots smaller than 15 μas in angular extent | about the size of the Sun at the distance of 700 pc. They are separated by 160+35 μas or 0.11 astronomical units. This is the smallest structure ever observed in a Galactic maser. The observed structure most likely can be explained in the model of turbulent vortices shed by an obstacle in a flow.
These results are published by A.M. Sobolev, J.M. Moran, M.D. Gray, A. Alakoz, H. Imai, W.A. Baan, A.M. Tolmachev, V.A. Samodurov, and D.A. Ladeyshchikov, 2018, ApJ, 856, id. 60.

RadioAstron image of NGC1275 reveals a wide and collimated jet structure on the scale of a few hundred gravitational radii

RadioAstron Nearby AGN Key Science Program has published its rst results in Nature Astronomy (Giovannini et al. 2018, https://www.nature.com/articles/s41550-018-0431-2). A 22 GHz space-VLBI image of the recently restarted parsec scale jet in 3C 84, a radio source located in the giant elliptical galaxy NGC1275 in the Perseus Cluster, transversely resolves the strongly edge-brightened young jet just 30 μas from the core { ten times closer to the central engine that in the previous ground-based studies. This corresponds to a de-projected linear distance of just a few hundred gravitational radii. Being able to resolve the jet and measure its collimation profile inside the acceleration region is important for testing the current jet formation models.
It was found that the jet in 3C 84 is surprisingly wide (Fig. 2), with a transverse radius greater than 250 gravitational radii. This implies that either the bright outer layer rapidly expands closer to the black hole or that this \sheath" is launched from the accretion disk.
Another major result of the paper is that the previously found, almost cylindrical collimation profile on the scales larger a few thousand gravitational radii extends down to a scale of a few hundred rg. It indicates a flat density profile of the external confining medium. The authors propose that the recently restarted jet in 3C 84 is shaped by shocked material of a cocoon forming around the jet - just like the kiloparsec scale jets are recollimated in a cylindrical shape before
they enter the leading hot spot.
The observations were made during a perigee passage in September 2013. In addition to Space Radio Telescope, more than two dozen ground radio telescopes, including the European VLBI Network together with the Russian Kvazar network, the Korean VLBI Network, Kalyazin and the NRAO telescopes Very Long Baseline Array, the Green Bank Telescope, and the phased Very Large Array, participated in the experiment.

Nikolai Kardashev ([email protected])
Yuri Kovalev ([email protected])
The RadioAstron project is led by the Astro Space Center of the Lebedev Physical Institute of the Russian Academy of Sciences and the Lavochkin Scientific and Production Association under a contract with the Russian Federal Space Agency, in collaboration with partner organizations in Russia and other countries.
To subscribe or un-subscribe to the Newsletter, use: http://asc-lebedev.ru/index2.php?engdep=22

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