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Proposal Identification No.:

P2067

Date Received:

2005-Feb-01 21:58:55

Technical Page
Proposal Type: General Category: Observation Category: Total Time Requested: Prop osal Title: Regular Pulsars Galactic 8 Hours

Estimation of Pulse Arrival Times for PSR B1937+21 Using Interstellar Holog-

raphy
ABSTRACT:
The millisecond pulsar B1937+21 is observed along a line of sight where refraction and diffraction in the ionised interstellar medium limit our ability to determine accurate pulse arrival times at low frequencies where the signal is strongest. We have develop ed a new technique for quantifying the timing error due to interstellar scattering, based on decomp osition of the dynamic sp ectrum into its constituent wave field comp onents. The dynamic sp ectrum contains information on the phase relationships b etween the various scattered waves ­ it is a hologram of the scattering centres ­ as well as their amplitude, Doppler-shift and delay (relative to the unscattered wave). B1937+21 is imp ortant test case to develop this technique owing to its strength as well as the presence of giant pulses which provide further information. We will record voltage samples over a wide-bandwidth and construct ~ high resolution dynamic sp ectra and pulse TOAs off-line. We will monitor the source at 430 MHz, and our corrected pulse TOAs will b e compared to the emphemeris generated from L-band timing data obtained in our regular timing programs.

Name Donald C Backer

Institution UC Berkeley

E-mail dbacker@astron.berkeley.edu

Phone 510-642-5128

Student no

Service Observing Request

Remot e Observing Request

X

None All of the observing run. Part of the observing run. Queue Observing X

No Maybe Yes

Instrument Setup
430 G 430 CH receiver

Atmospheric Observation Instruments:

1


Sp ecial Equipment or setup: We will be using either the Gregorian feed at 430 MHz, or the line feed, depending on interference level and other runtime factors. We will be using the ASP backend for our observations.

RFI Considerations Frequency Ranges Planned

2