Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/vscience/schedule/2013Spring/RobishawtagA2764.pdf Дата изменения: Tue Sep 11 04:14:23 2012 Дата индексирования: Tue Feb 5 00:05:25 2013 Кодировка: Поисковые слова: magnetic field

Proposal Identification No.:

A2764 Arecibo Observatory

Date Received: 2012-Sep-04 03:21:19 William E. Gordon Telescope Observing Time Request COVER SHEET

Section I - General Information
Submitted for Sep 1 2012. This proposal has not been submitted before. Proposal Type: General Category: Sub-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 Astronomy Spectroscopy Galactic 80 0 00:30 less than 100 GB

HINSA: A Promising New Tool for Probing Magnetic Fields in the CNM

The magnetic field is one of the most important parameters affecting molecular clouds and star formation. Unfortunately, however, its measurement in molecular clouds remains an exceedingly difficult task, particularly in dark clouds. Multiple methods have been used to estimate the magnetic field in the Taurus molecular cloud complex and each returns a field of strength 5 to 10 microgauss. But none of these methods is as direct as the Zeeman effect. We propose to use a new tool for probing magnetic fields in molecular clouds: HI Narrow Self-Absorption (HINSA). We choose 4 positions in 2 dark clouds in Taurus and request 80 hours of Arecibo time to detect Zeeman splitting in deep HINSA features down to a limiting magnetic field strength of 0.6 microgauss. Outreach Abstract: When a radio wave is emitted in the space between stars, a special fingerprint can be left on the radio wave if there was a strong magnetic field in the vicinity of the location where the radio wave comes from. We are looking for this special fingerprint in radio waves that come from the very dark clouds of gas where one day bright young stars will be born. If there is a strong magnetic field in these stellar nurseries, then it will take longer for a star to be born; a weak magnetic field and the star will turn on much more quickly. We want to learn how magnetic fields affect the formation of stars and we will use Arecibo to investigate this cosmic mystery.

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Name Timothy Robishaw

Di Li

Institution Dominion Radio Astrophysical Observatory National Astronomical Observatories, Chinese Academy of Sciences

E-mail tim.robishaw@nrc-cnrc.gc.ca

Phone +1 250 4972350 86-1064806305

Student no

ithaca.li@gmail.com

no

Additional Authors
Carl Heiles heiles@astro.berkeley.edu Lei Zhu lzhupku@gmail.com

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 preferred.

Begin ­ End Interval­Interval 03:10 ­ 04:40 ­ ­ ­

Days Needed at This Interval 54

Time Constraints (Must Be Justified in the Prop osal Text) Avoid Feb 8 ­ Mar 01 2013 if possible.

Section I I I - Instruments Needed
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L-wide Atmospheric Observation Instruments:

Sp ecial Equipment or setup:

none

Section IV - RFI Considerations Frequency Ranges Planned
1610-1720

Section V - Observing List Target List
L1534a 04:41:46 +25:41:24 03:23-04:42 L1534b 04:40:16 +25:35:24 03:22-04:41 L1527A-1a 04:39:53 +25:45:00 03:21-04:40 L1527A-1b 04:38:23 +25:39:00 03:20-04:39

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