Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/vscience/schedule/tpfiles/ArayatagA2411tp.pdf Дата изменения: Wed Jun 11 18:58:53 2008 Дата индексирования: Wed Jan 14 10:52:43 2009 Кодировка: Поисковые слова: http astrokuban.info astrokuban

Proposal Identification No.:

A2411

Date Received:

2008-Jun-02 17:21:10

Technical Page
Proposal Type: General Category: Sub-Category: Observation Category: Total Time Requested: Minimum Useful Time: Prop osal Title: Long-term Astronomy Spectroscopy Galactic 37 Hours 1

Periodic Maser Flares in IRAS18566+0408: Continuing the Arecibo Monitoring

Program
ABSTRACT:
Using Arecibo we discovered H2CO maser emission in IRAS18566+0408, a very young massive stellar ob ject. Subsequent observations resulted in the detection of the first short-term flare of an H2CO maser. Two years ago we started a monitoring program of the H2CO maser with Arecibo that, together with VLA observations, resulted in the detection of three more flare events. The flares appear to be periodic; we have discovered the first periodic H2CO maser flare system. We also discovered correlated variability between the H2CO and CH3OH masers in the region. After a comprehensive study of IRAS18566+0408 using Arecibo, (E)VLA, MERLIN, GBT, as well as Spitzer, we have found evidence that the flares are tracing changes in the infrared field, perhaps caused by pulsations of the massive protostar. If this is confirmed, the periodic maser flares may be giving us fundamental new insight into the structure of massive protostars. Here we propose to continue our Arecibo monitoring program to study the next flare event with high temporal resolution, and investigate long term changes in the periodicity and peak intensity of the flares.

Name Esteban D Araya

Institution University of Mexico

New

E-mail earaya@nrao.edu

Phone 505 252 3747

Student no

Remote Observing Request

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

Instrument Setup
C C-high

Atmospheric Observation Instruments: 1


Sp ecial Equipment or setup:

none

RFI Considerations Frequency Ranges Planned
4820 - 4840 (H2CO 6cm) 6660 - 6680 (CH3OH 6.7 GHz)

2