ATCA non-detection at 8.7 GHz of the Millisecond X-ray Pulsar SWIFT J1756.9-2508
ATel #1128; A. Possenti (INAF-OACagliari), M. Murgia (INAF-OACagliari), J. Reynolds (ATNF), F. Camilo (Columbia Univ.), L. Burderi (Univ. Cagliari), T. Di Salvo (Univ. Palermo), A. Antonelli (INAF-OARoma), E. Bozzo (INAF-OARoma), M. Burgay (INAF-OACagliari), N. D'Amico (INAF-OACagliari), E. Gallo (UCSB), R. Iaria (Univ. Palermo) G. L. Israel (INAF-OARoma), M. T. Menna (INAF-OARoma), A. Papitto (INAF-OARoma/Univ. Tor Vergata), A. Riggio (Univ. Cagliari), V. Testa (INAF-OARoma)
on 4 Jul 2007; 08:54 UT
Credential Certification: Andrea Possenti (possenti@oa-cagliari.inaf.it)
Subjects: Radio, Neutron Star, Transient, Pulsar
We did not detect the Millisecond X-ray Pulsar SWIFT J1756.9-2508
(ATel #1105, #1107, #1108, #1111, #1114, #1117) during an observation
performed on June 26, 2007 (08:55 to 19:00 UT) at the Australia
Telescope Compact Array (ATCA) under the TOO proposal CX136.
We used array configuration 6C, a central frequency of 8.7 GHz, a
bandwidth of 256 MHz, and observed for ~12 ks on-source (2 of the 6
antennae were unavailable). The synthesized beam was 0.95 arcsec x
1.85 arcsec. The flux calibrator 0823-500 and the phase calibrator
1752-225 (~600 milliJy/beam at 8.7 GHz) were used. We pointed at the
position reported in ATel #1111 (RA = 17h 56m 57.1s Dec=-25d 06m
26.7s, epoch 2000.0). No pointlike source was found within the 90%
confidence positional error circle of the X-ray source (3.5" radius,
ATel #1111), down to a flux density level (~0.27 milliJy/beam)
corresponding to 5 times the rms noise.
