Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/vscience/schedule/tpfiles/JonestagP2721tp.pdf Дата изменения: Tue Mar 6 22:45:29 2012 Дата индексирования: Fri Feb 28 23:13:49 2014 Кодировка: Поисковые слова: http astrokuban.info astrokuban

Proposal Identification No.:

P2721

Date Received:

2012-Mar-01 18:30:54

Technical Page
Proposal Type: General Category: Observation Category: Total Time Requested: Minimum Useful Time: Prop osal Title: ABSTRACT: Regular Pulsars Galactic 8 Hours 1 hour

NANOGrav precision timing: Demonstrating real-time cyclic spectroscopy

The NANOGrav collaboration is initiating a systematic study of the ISM properties toward the best-timing pulsars in our source list. Our mid-term goal is to reduce timing noise in these pulsars down to the 10 ns level. Currently, our best-timing pulsar, J1713+0747, has an rms timing residual of 40 ns. We aim to build upon the techniques developed in previous proposals (P2676, Dolch et al.; P2627, Palliyaguru et al.) to characterize and correct for inhomogeneities in the ISM which directly impact pulsar timing residuals. Previous observations used to demonstrate the cyclic spectroscopy developed by members of our team (Demorest, van Straten) required baseband data recording which limits the practical observation bandwidth and results in large, difficult to manage datasets. We propose to demonstrate real-time computation of the cyclic spectrum by using a specialized FPGA-based filterbank and by taking advantage of the computational power now available in the GPU cluster which is part

Name Glenn Jones

Institution NRAO / Caltech

E-mail glenn.caltech@gmail.com

Phone 626 395 4509

Student no

Remote Observing Request

X

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

Instrument Setup
430 G L-wide 327

Atmospheric Observation Instruments:

Description of Observer Equipment: We plan to use a ROACH FPGA board present at the observatory connected by 10 gigabit ethernet to the PUPPI cluster via spare ports on its network switch. 1


Sp ecial Equipment or setup: hardware is flexible and can acce convenient. We will be using the is relatively small and will result

We will need to connect a pair of IF signals to the ROACH. Our pt almost any IF available. The ALFA IF frequency range is particularly PUPPI GPU cluster for these observations. Our final data rate to disk in <100 GB of data.

RFI Considerations Frequency Ranges Planned
307 - 347 MHz 418 - 442 MHz 1150 - 1730 MHz This proposal requires coordination with Punta Salinas radar within the band 1222-1381 MHz..

2