Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/vscience/schedule/2016Spring/MacquarttagP3030.pdf Дата изменения: Tue Sep 15 04:38:18 2015 Дата индексирования: Mon Apr 11 17:24:07 2016 Кодировка: Поисковые слова: mercury surface

Proposal Identification No.:

P3030 Arecibo Observatory

Date Received: 2015-Sep-01 07:42:29 William E. Gordon Telescope Observing Time Request COVER SHEET

Section I - General Information
Submitted for Sep 1 2015. This proposal has not been submitted before. Proposal Type: General Category: Observation Category: Time Requested this semester: Hours already used for this pro ject: Additional Hours required to complete pro ject: Minimum Useful Time: Expected Data Storage: Prop osal Title: ABSTRACT: Regular Pulsars Galactic 10 0 2 hour over 500 GB

Towards a new model of interstellar turbulence using pulsar B0834+06

Our previous speckle image towards the pulsar B0834+06 revealed features in the sub-AU structure of the interstellar medium that have engendered a rethink of the nature of interstellar turbulence. We now wish to make a succession of observations of the pulsar B0834+06, supported by HSA two-dimensional speckle imaging, to track the dynamics of this underlying small-scale structure. This will directly tests key aspects of several newly-proposed models of interstellar structure. It will distinguish between the two ma jor competing models in which the speckle image structure is either caused by (i) the turbulent cascade of energy associated with velocity and magnetic field fluctuations in the interstellar plasma or (ii) static structures in the ISM, such as those associated with current sheets and sites of active magnetic reconnection. Our observations will also provide new insight into the nature of Extreme Scattering Events, one of which was revealed by our previous work. Outreach Abstract: The gas that lies in between the stars is turbulent, causing the radiation from pulsars to twinkle. The nature of the turbulence that drives the scintillations in pulsars remains an open question. In 2010, we made the first-ever instantaneous image of this turbulence using a new technique, called speckle astrometry. This work revealed a picture of structures in interstellar space that were unanticipated and which were not explainable in terms of existing models of interstellar dynamics. Here we plan to take the next step in understanding the nature of the turbulence by directly measuring the evolution of these structures with time. We hope to then understand the dynamics that lead to the formation of these structures in the first place. A secondary aim is to use the turbulence in the interstellar medium as an enormous interferometer - with an angular resolution of 50 picoarcseconds - to directly resolve the site of the pulsar emission in one of the brightest pulsars in the radio sky.

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Name Jean-Pierre Macquart Ue-Li Pen

Institution ICRAR Canadian Institute for Theoretical Astrophysics

E-mail J.Macquart@curtin.edu.au pen@cita.utoronto.ca

Phone +61892662377 +1416 976477

Student no no

Additional Authors
Franz Kirsten, franz.kirsten@curtin.edu.au Rober Main, main@astro.utoronto.ca Niloufar Afsariardchi, afsariardchi@astro.utoronto.ca Marten van Kerkwijk, mhvk@astro.utoronto.ca Walter Brisken, wbrisken@nrao.edu Adam Deller, deller@astron.nl Olaf Wucknitz, wucknitz@mpifr-bonn.mpg.de Alex Kraus, akraus@mpifr-bonn.mpg.de Paul Demorest, pdemores@nrao.edu

This work is not part of a thesis.

Remote Observing Request

Observer will travel to AO Remote Observing X In Absentia (instructions to operator)

Section I I - Time Request
The following times are in LST. For these observations night-time is not needed.

Begin ­ End Interval­Interval 07:40 ­ 09:40 ­ ­ ­

Days Needed at This Interval 5

Time Constraints (Must Be Justified in the Prop osal Text) We request five observations in total, interleaved with our HSA observations. The HSA observations are planned to have the first two observations separated by a week, and the remaining two observations 2


separated by an interval of 3-4 weeks. We request one very short time spacing (i.e. in the shortest HSA gap) and the rest interleaved in a manner that keeps all the gaps below 2 weeks. To be explicit, an example of such a schedule would be: HSA-1 ­ Arecibo-1 (3d later) ­ HSA-2 (5d later (i.e. 8d after HSA-1)) ­ Arecibo-2 (8d later) ­ Arecibo-3 (12d later) ­ HSA-3 (12d later) ­ Arecibo-4 (12d later) ­ Arecibo-5 (12d later) ­ HSA-4 (12 later).

Section I I I - Instruments Needed
327 Atmospheric Observation Instruments:

Sp ecial Equipment or setup: We would like to record minimal possible bandwidth of 100MHz (dual-polarisation, recored in baseband mode without any channelisation. Per raw data. We will provide the required disks ahead of time

with the PUPPI backend utilising only the 8-bit recording). We would like the data to be observation we will thus aquire about 3TB of .

Section IV - RFI Considerations Frequency Ranges Planned

Section V - Observing List Target List
B0834+06, RA=08h37m05.642s Dec=+06d10'14.56", LST-range=07:34:38-09:41:11

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