Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/vscience/schedule/2015Fall/WolszczantagP2997.pdf Дата изменения: Sat Mar 7 21:34:24 2015 Дата индексирования: Mon Apr 11 17:06:42 2016 Кодировка: Поисковые слова: m 106

Proposal Identification No.:

P2997 Arecibo Observatory

Date Received: 2015-Feb-28 15:54:08 William E. Gordon Telescope Observing Time Request COVER SHEET

Section I - General Information
Submitted for Mar 1 2015. This proposal has not been submitted before. Proposal Type: General 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: Director Discretionary Time Pulsars Galactic 40 0 0 0 2 less than 100 GB

High-cadence timing observations of the planets pulsar, PSR B1257+12

We propose to resume timing observations of the planets pulsar, PSR B1257+12, with the Arecibo telescope at 430 MHz and L-band frequencies, using the PUPPI backend. We would like to conduct one-month, high-cadence observations to obtain 18 pulse arrival times that should allow us to phase connect our new measurements to the existing data set spanning the period from 1991 through 2009. The new data will also tell us how much improvement in timing precision can be achieved with the PUPPI backend, compared to the 3.5 microsecond long-term, post-fit residual obtained with the Penn State Pulsar Machine (PSPM) for the post-upgrade, 1997-2009 data. If a 1 microsecond precision can be attained, it will be possible to use PSR B1257+12 and other solitary millisecond pulsars visible from Arecibo to explore the currently untouched part of the neutron star planet parameters space involving low-mass bodies in short-period orbits. Outreach Abstract: The 6.2 millisecond pulsar, PSR B1257+12, hosts the first confirmed extrasolar planetary system, discovered in 1992. These three planets have been formed in a protoplanetary disk, just like planets orbiting normal, Sun-like stars. Curiously, no additional, disk-created neutron star planets have been detected so far, and the existing limits from the published long-term timing programs have excluded Earth- mass planets for many millisecond pulsars. Of course, this may be simply because such planets are extremely rare. However, there are theoretical grounds to believe that the real reason could have to do with a possibility that these planets have very low, Moon-like masses and very short orbital periods. As the existing pulsar timing pro jects have no sensitivity to detect such planets, we propose to resume the timing of PSR B1257+12 with the much improved hardware, to explore possibilities to achieve the timing precision needed to discover them.

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Name Alexander Wolszczan Andrew D Seymour

Institution Penn State University Arecibo Observatory

E-mail alex@astro.psu.edu seymour.andrew@gmail.com

Phone 814 863 1756 787 878 2612 ext. 254

Student no no

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 12 ­ ­ ­ ­ 14

Days Needed at This Interval 18

Time Constraints (Must Be Justified in the Prop osal Text) This is a high-cadence observation pro ject requesting all the measurements to take place in the following sequence: 7 consecutive days, 2 hours each, followed by 11 every other day runs, 2 hours each. As we plan to engage a summer student in this pro ject and need to synchronize the data taking with a visit to the AO of one of us (AW), we request the time to be possibly allocated in July 2015.

Section I I I - Instruments Needed
430 G L-wide

Atmospheric Observation Instruments: 2


Sp ecial Equipment or setup:

none

Section IV - RFI Considerations Frequency Ranges Planned
1.15 - 1.73 GHz 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
RA = 13:00:03.1 DEC = 12:40:55.6

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