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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

599 results found.

  1. SGR 0501+4516: Proximity to supernova remnant HB9
  2. Enhanced Swift-XRT position of SGR 0501+4516
  3. SGR 0501+4516: GMRT Radio Observation at 618 MHz
  4. SGR 0501+4516: Swift XRT measure of the spin period
  5. SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
  6. Soft Gamma Repeater SGR 0501+4516: GBM Detection of multiple bursts
  7. Suzaku ToO Observation of SGR 0501+4516
  8. SGR 0501+4516: radio pulsar searches with GBT and WSRT
  9. Konus-Wind observations of new SGR 0501+4516
  10. INTEGRAL ToO Observation of SGR0501+4516
  11. Radio Detection of SGR 0501+4516
  12. SGR 0501+4516: MDM Optical Observations
  13. SGR 0501+4516: Astrotel-Caucasus optical observations
  14. SGR 0501+4516: UKIRT detection of possible infra-red counterpart
  15. SGR 0501+4516: WSRT Radio Observations
  16. Trigger 321551: Continued Large Flaring of SGR 0501+4516
  17. SGR 0501+4516: optical observations
  18. Swift Trigger 321481: A Large Flare from SGR 0501+4516
  19. SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
  20. Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
  21. Third event from SGR 0501+4516
  22. GRB 080822 (SGR 0501+4516): archival optical observations
  23. New Soft Gamma Repeater 0501+4516 was GRB 080822
  24. SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
  25. Konus-Wind observation of reactivation of SGR 1627-41
  26. Reactivation of SGR 1627-41
  27. Disregard the "GRB 071126" position
  28. GRB 071017: a SHORT GRB detected by INTEGRAL
  29. INTEGRAL ToO observations of SGR1806-20
  30. SGR1806-20: Swift-BAT detection of enhanced activity
  31. Intense burst from SGR 1806-20 detected on September 7
  32. Swift detection of a outburst from SAX J1810.8-2609
  33. AGILE-ACS position for the SGR 1806-20 July 27 burst
  34. Intense burst from SGR 1806-20 detected on July 27
  35. Suzaku ToO observation of SGR 1806-20
  36. INTEGRAL ToO Observation of SGR1806-20
  37. long burst from SGR 1806-20 detected on March 26
  38. GRB 070201: clarification on localization and Konus-Wind spectra
  39. IPN localization of very intense short GRB 070201
  40. Two bright bursts from SGR 1806-20 detected with IBAS
  41. Image of the dust-scattering halo around SGR 1806-20
  42. Second VLA limit on new radio point source in SGR 1806-20
  43. A dust-scattering halo detected around SGR 1806-20
  44. VLA Upper Limit on Outburst of SGR 1806-20
  45. GRB060806 is similar to previous activity of SGR1806-20
  46. BAT Trigger #214277 is SGR 1900+14
  47. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  48. SGR 1900+14: Swift detection of an outburst
  49. SGR 1900+14: BAT observations
  50. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  51. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  52. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  53. SGR 1900+14: Swift-BAT detection of a bright outburst
  54. SGR 1900+14: CORRECTION to GCN 4923
  55. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  56. SGR 1900+14: Swift detection of renewed activity
  57. GRB 060218: rebrightening
  58. An extraordinary long burst on December 3 from SGR1806-20
  59. Possible resuming of the SGR 1806-20 activity
  60. GRB050925: analysis of the XMM-Newton observation
  61. GRB/SGR 050925: XMM-Newton ToO observation
  62. GRB051103: MASTER: OT limit and host galaxy candidates
  63. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  64. SGR 1806-20: continued moderate activity seen with INTEGRAL
  65. GRB/SGR 050925: IR Observations
  66. GRB050925: Swift-BAT detection of a short burst
  67. GRB 050906: Swift-BAT refined analysis
  68. GRB 050906: Bright galaxy in BAT error box
  69. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  70. Detection of an intermediate burst from SGR 1806-20 on August 8
  71. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  72. Konus-Wind observation of an intermediate burst from SGR 1806-20
  73. Renewal of SGR 1806-20 activity
  74. Ongoing activity of SGR 1806-20 after the giant flare
  75. SGR 1806-20: GMRT results at 240 MHz band.
  76. SGR 1806-20: low frequency GMRT results of 2005 Jan 16.
  77. SGR 1806-20: RXTE/PCA pulse frequency during flare
  78. SGR 1806-20: Further VLA Observations
  79. SGR 1806-20: Further low frequency GMRT results
  80. SGR 1806-20: Further VLA Observations
  81. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  82. Further VLA observations of SGR 1806-20
  83. SGR 1806-20 and extragalactic short-duration GRBs
  84. Further ATCA observations of SGR 1806-20
  85. Fourth Epoch VLA observations of SGR 1806-20
  86. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  87. SGR 1806-20: Temporal and Spectral behavior of radio transient
  88. ATCA observations of SGR 1806-20
  89. SGR 1806-20, RHESSI observations of the 041227 giant flare
  90. Third epoch observations of SGR 1806-20 with VLA
  91. Second Epoch VLA observations of SGR 1806-20
  92. Second-epoch VLA observations of SGR 1806-20
  93. SGR1806: Detection of a Sudden Ionospheric Disturbance
  94. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  95. VLA observations of SGR 1806-20
  96. SGR1806 VLA Observations
  97. VLA observations of SGR 1806-20
  98. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  99. Detection of the SGR 1806-20 giant outburst back-scattered by the
  100. The giant outburst from SGR 1806-20

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