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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"

608 results found.

  1. SGR 0501+4516: Detection of possible optical counterpart
  2. SGR 0501+4516: WHT observations of the possible near-infrared counterpart
  3. VLA non-detection of SGR 0501+4516
  4. Radio Detection of SGR 0501+4516: Retraction
  5. SGR 0501+4516: XMM-Newton monitoring schedule
  6. SGR 0501+4516: Decline in Activity
  7. SGR 0501+4516: Proximity to supernova remnant HB9
  8. Enhanced Swift-XRT position of SGR 0501+4516
  9. SGR 0501+4516: GMRT Radio Observation at 618 MHz
  10. SGR 0501+4516: Swift XRT measure of the spin period
  11. SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
  12. Soft Gamma Repeater SGR 0501+4516: GBM Detection of multiple bursts
  13. Suzaku ToO Observation of SGR 0501+4516
  14. SGR 0501+4516: radio pulsar searches with GBT and WSRT
  15. Konus-Wind observations of new SGR 0501+4516
  16. INTEGRAL ToO Observation of SGR0501+4516
  17. Radio Detection of SGR 0501+4516
  18. SGR 0501+4516: MDM Optical Observations
  19. SGR 0501+4516: Astrotel-Caucasus optical observations
  20. SGR 0501+4516: UKIRT detection of possible infra-red counterpart
  21. SGR 0501+4516: WSRT Radio Observations
  22. Trigger 321551: Continued Large Flaring of SGR 0501+4516
  23. SGR 0501+4516: optical observations
  24. Swift Trigger 321481: A Large Flare from SGR 0501+4516
  25. SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
  26. Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
  27. Third event from SGR 0501+4516
  28. GRB 080822 (SGR 0501+4516): archival optical observations
  29. New Soft Gamma Repeater 0501+4516 was GRB 080822
  30. SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
  31. Konus-Wind observation of reactivation of SGR 1627-41
  32. Reactivation of SGR 1627-41
  33. GRB 080310: PAIRITEL detection and PAIRITEL+KAIT+UVOT SED
  34. Disregard the "GRB 071126" position
  35. GRB 071017: a SHORT GRB detected by INTEGRAL
  36. INTEGRAL ToO observations of SGR1806-20
  37. SGR1806-20: Swift-BAT detection of enhanced activity
  38. Intense burst from SGR 1806-20 detected on September 7
  39. Swift detection of a outburst from SAX J1810.8-2609
  40. AGILE-ACS position for the SGR 1806-20 July 27 burst
  41. Intense burst from SGR 1806-20 detected on July 27
  42. GRB070521 - SDSS Pre-Burst Observations
  43. Suzaku ToO observation of SGR 1806-20
  44. INTEGRAL ToO Observation of SGR1806-20
  45. long burst from SGR 1806-20 detected on March 26
  46. GRB 070311: Late Central Engine Activity Optical Flare??
  47. GRB 070201: clarification on localization and Konus-Wind spectra
  48. IPN localization of very intense short GRB 070201
  49. Two bright bursts from SGR 1806-20 detected with IBAS
  50. Image of the dust-scattering halo around SGR 1806-20
  51. Second VLA limit on new radio point source in SGR 1806-20
  52. A dust-scattering halo detected around SGR 1806-20
  53. VLA Upper Limit on Outburst of SGR 1806-20
  54. GRB060806 is similar to previous activity of SGR1806-20
  55. BAT Trigger #214277 is SGR 1900+14
  56. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  57. SGR 1900+14: Swift detection of an outburst
  58. SGR 1900+14: BAT observations
  59. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  60. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  61. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  62. SGR 1900+14: Swift-BAT detection of a bright outburst
  63. SGR 1900+14: CORRECTION to GCN 4923
  64. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  65. SGR 1900+14: Swift detection of renewed activity
  66. GRB 060218: rebrightening
  67. An extraordinary long burst on December 3 from SGR1806-20
  68. Possible resuming of the SGR 1806-20 activity
  69. GRB050925: analysis of the XMM-Newton observation
  70. GRB/SGR 050925: XMM-Newton ToO observation
  71. GRB051103: MASTER: OT limit and host galaxy candidates
  72. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  73. SGR 1806-20: continued moderate activity seen with INTEGRAL
  74. GRB/SGR 050925: IR Observations
  75. GRB050925: Swift-BAT detection of a short burst
  76. GRB 050906: Swift-BAT refined analysis
  77. GRB 050906: Bright galaxy in BAT error box
  78. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  79. Detection of an intermediate burst from SGR 1806-20 on August 8
  80. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  81. Konus-Wind observation of an intermediate burst from SGR 1806-20
  82. Renewal of SGR 1806-20 activity
  83. Ongoing activity of SGR 1806-20 after the giant flare
  84. SGR 1806-20: GMRT results at 240 MHz band.
  85. SGR 1806-20: low frequency GMRT results of 2005 Jan 16.
  86. SGR 1806-20: RXTE/PCA pulse frequency during flare
  87. SGR 1806-20: Further VLA Observations
  88. SGR 1806-20: Further low frequency GMRT results
  89. SGR 1806-20: Further VLA Observations
  90. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  91. Further VLA observations of SGR 1806-20
  92. SGR 1806-20 and extragalactic short-duration GRBs
  93. Further ATCA observations of SGR 1806-20
  94. Fourth Epoch VLA observations of SGR 1806-20
  95. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  96. SGR 1806-20: Temporal and Spectral behavior of radio transient
  97. ATCA observations of SGR 1806-20
  98. SGR 1806-20, RHESSI observations of the 041227 giant flare
  99. Third epoch observations of SGR 1806-20 with VLA
  100. Second Epoch VLA observations of SGR 1806-20

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