Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/vscience/schedule/2015Spring/WolszczantagA2944.pdf Дата изменения: Tue Sep 9 17:24:49 2014 Дата индексирования: Mon Apr 11 17:38:23 2016 Кодировка:

Proposal Identification No.:

A2944 Arecibo Observatory

Date Received: 2014-Sep-01 06:28:03 William E. Gordon Telescope Observing Time Request COVER SHEET

Section I - General Information
Submitted for Sep 1 2014. This proposal has not been submitted before. Proposal Type: General Category: Sub-Category: Observation Category: Time Requested this semester: Hours Next Semester: Hours already used for this pro ject: Additional Hours required to complete pro ject: Minimum Useful Time: Expected Data Storage: Prop osal Title: Regular Astronomy Spectroscopy Galactic 36 24 0 2 hours 100-500 GB

Continuation of the timing of the periodically flaring ultracool dwarf, TVLM

513-46546
ABSTRACT: We propose to continue timing observations of an ultracool dwarf, TVLM 513-46546, with the Arecibo telescope at 5 GHz and the Mock spectrometer, to obtain broadband, high resolution dynamic spectra of the source. Previous observations have shown that timing of the periodic flares from this star can be used to monitor the behavior of the active regions in the magnetosphere that generate the flares. They also suggest that the observed, small changes in the apparent period and phase of the flares can be related to a differential rotation of the star. However, an unambiguous characterization of this process requires long-term, systematic monitoring observations, avoiding large gaps in the data. In addition, the observed high quality dynamic spectra of the flares can be used in combination with the timing data to produce diagnostics of both the geometry of the magnetic field and the physical conditions in the magnetosphere in an unprecedented detail. Outreach Abstract: Ultracool dwarfs, like TVLM 513-46546 and brown dwarfs, live at the border between stars and giant planets. Because their physics is similar to that of the giant planets, but they are much brighter and easier to observe, the results from studies of ultracool dwarfs can also be applied to extrasolar planets. Our timing observations of the periodic radio flares from TVLM 513 have a potential to dramatically improve our knowledge of the physical characteristics of this ob ject. Results from these observations will also improve our understanding of the physical properties of brown dwarfs and large planets.

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Name Alexander Wolszczan Gabriel Ortiz Pena

Institution Penn State University Penn State University

E-mail alex@astro.psu.edu gho5001@psu.edu

Phone 814 863 1756 814 865 0418

Student no U

This work is not part of a thesis.

Remote Observing Request

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

Section I I - Time Request
The following times are in LST. For these observations night-time is .

Begin ­ End Interval­Interval 14:00 ­ 16:00 ­ ­ ­

Days Needed at This Interval 18

Time Constraints (Must Be Justified in the Prop osal Text) Six consecutive days are requested initially, followed by biweekly observations over the period of six months. No need to restrict observations to nighttime.

Next Semester Time Request

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Begin ­ End Interval­Interval 14:00 ­ 16:00 ­ ­ ­

Days Needed at This Interval 12

Time Constraints (Must Be Justified in the Prop osal Text) Biweekly observations over the period of six months

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

Sp ecial Equipment or setup:

none

Section IV - RFI Considerations Frequency Ranges Planned

Section V - Observing List Target List
RA = 15 01 08 DEC = +22 50 02

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