Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/vscience/schedule/2013Spring/SaltertagA2766.pdf Дата изменения: Tue Sep 11 04:14:23 2012 Дата индексирования: Mon Feb 4 22:42:16 2013 Кодировка: Поисковые слова: arp 220

Proposal Identification No.:

A2766 Arecibo Observatory

Date Received: 2012-Sep-04 17:48:36 William E. Gordon Telescope Observing Time Request COVER SHEET

Section I - General Information
Submitted for Sep 1 2012. This proposal has been submitted before. The previous proposal number is A2713 (partly). 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 Continuum 7.5 hr 7.5 hr 0 2.5 hr less than 100 GB

Monitoring a Remarkable Spectral Line/Continuum Outburst in LIRG NGC 660

Previous Arecibo observations have serendipitously discovered a radio continuum and spectral-line outburst in the nearby morphologically peculiar galaxy, NGC 660. A new continuum component with GHz-Peaked Spectrum (GPS) emission (Speak 0.5 Jy at 5 GHz) has emerged between epochs 2008.0 and 2012.0. This has been accompanied by the parallel development of excited-OH maser emission/absorption in the 4660, 4750 and 4765-MHz transitions. Also detected are a new component in the absorption spectrum of H2 C O, and conjugate L-band satellite lines of the OH radical. Such rapid change in the molecular medium in an external galaxy is rare, but could have been initiated by supernova shocks or interaction of nuclear radio jets with interstellar GMCs. Monitoring this unusual event provides a natural way to investigate the physical and chemical evolution of this galaxy, and would have implications for models for the evolution of starburst systems. We therefore request observations of one transit of NGC 660 (2.5 hr) every other month for the next year. Total time request is 15 hours. Outreach Abstract: The Space in between the billions of stars in a galaxy is filled with gaseous material, called the interstellar medium (ISM). Much of it 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 the GMCs, evolve and some of those can explode as supernovae at the end of their lives, contributing more complex material 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 3 years. While a few other galaxies have also shown similar events, these phenomena are rather rare. Hence, in this proposal, we are requesting time to monitor NGC 660 every other month for the next year. For this purpose, we will need 15 hours of total telescope time.

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Name Christopher J Salter Tapasi Ghosh

Institution Arecibo Observatory Arecibo Observatory

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

Phone 7878782612 X 281 7878782612 X289

Student no no

Additional Authors
Robert Minchin Arecibo Observatory rminchin@naic.edu emomjian@nrao.edu Emmanuel Momjian EVLA - NRAO

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) Please schdule one transit every two months.

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) Please schdule one transit every two months.

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

Sp ecial Equipment or setup:

none

Section IV - RFI Considerations Frequency Ranges Planned
4300 - 5300

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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