Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/vscience/schedule/2014Spring/SaltertagA2766.pdf Дата изменения: Fri Sep 6 19:44:16 2013 Дата индексирования: Sat Mar 1 01:02:28 2014 Кодировка: Поисковые слова: galactic cluster

Proposal Identification No.:

A2766 Arecibo Observatory

Date Received: 2013-Sep-03 16:40:47 William E. Gordon Telescope Observing Time Request COVER SHEET

Section I - General Information
Submitted for Sep 1 2013. 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: ABSTRACT: Regular Astronomy Spectroscopy Extragalactic 7.5 7.5 0 2.5 hr less than 100 GB

Continued Monitoring of the Spectral Line/Continuum Outburst in NGC660.

A radio continuum and spectral-line outburst has been serendipitously discovered by us in NGC660. From Feb. 2013, bi-monthly monitoring of this remarkable ob ject has been started, with four observing epochs completed to date. Variability of the continuum spectrum, and of the detailed OH emission/absorption spectra at 4660, 4750, and 4765 MHz have been followed over this period. Such rapid changes in the molecular emission from the nuclear region of a galaxy are unprecedented. To delineate the physical model of this complicated starburst system further, we are supplementing these Arecibo observations with milliarcsecond-resolution HSA (VLBI) line and continuum imaging at yearly intervals (with Arecibo in the array). The VLBI images reveal a recent nuclear outburst with the OH features being associated with the outburst hotspots. The Arecibo single-dish and HSA monitoring are highly complimentary and a further year of Arecibo monitoring is requested here. Outreach Abstract: The space between the billions of stars in a galaxy is filled with gaseous material, called the interstellar medium (ISM). Much of this ISM is neutral hydrogen, but there are also giant molecular clouds (GMC) and gaseous nebulae with ionized and molecular gas and dust particles. Stars start their lives in GMCs, evolve, and the most massive can explode as supernovae at the end of their lives contributing heavy elements back to the ISM. Such processes usually occur over time spans of millions of year. In the unusual galaxy called NGC 660, we have discovered a sudden change in its radio energy output, and molecular signatures over just a few years. Such phenomena are rare. During the past year, we have monitored this ob ject every two months from Arecibo and found that it varies even over such a short period. In this proposal, we are requesting observing time to continue monitoring it for a further year.

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Name Christopher J Salter Tapasi Ghosh

Institution Arecibo Observatory Arecibo Observatory

E-mail csalter@naic.edu tghosh@naic.edu

Phone 787 878 2612 X 281 787 878 2612 X 289

Student no no

Additional Authors
Robert Minchin Arecibo Observatory 787 878 2612 x 283 rminchin@naic.edu Emmanuel Momjian EVLA-NRAO emomjian@nrao.edu

This work is not part of a thesis.

Remote Observing Request

X

Observer will travel to AO Remote Observing 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 0.5 ­ ­ ­ ­ 3.0

Days Needed at This Interval 3

Time Constraints (Must Be Justified in the Prop osal Text)

Next Semester Time Request

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Begin ­ End Interval­Interval 0.5 ­ ­ ­ ­ 3.0

Days Needed at This Interval 3

Time Constraints (Must Be Justified in the Prop osal Text)

Section I I I - Instruments Needed
L-wide C S-low X-band S-high C-high

Atmospheric Observation Instruments:

Sp ecial Equipment or setup: We would like availability of as many of our requested receivers as possible. However the C-band receiver is essential.

Section IV - RFI Considerations Frequency Ranges Planned
1 - 10 GHz

This proposal requires Iridium RFI protection at 1612 MHz between 10pm and 6am EST. This proposal requires coordination with Punta Salinas radar within the band 1222-1381 MHz.. This proposal requires coordination with GPS L3 at 1381 MHz.

Section V - Observing List Target List
NGC660 01 43 02.4 +13 38 42 BP Cal 01 41 09.1 +13 53 28

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