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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"

866 results found.

  1. SGR 1806-20: Fermi GBM detection
  2. SGR 0501+4516: optical observations in August
  3. GRB 081101 (or SGR 0623-0006 ): Fermi GBM detection
  4. SGR 0623-0006 or GRB 081101: Swift-XRT refined analysis
  5. SGR 0623-0006 or GRB 081101: Swift-BAT/-XRT refined analysis
  6. Swift-BAT triggered on a probable GRB 081101 (trigger=333320)
  7. GRB 081024: Swift detection of a burst
  8. INTEGRAL ToO observation of the AXP 1E 1547.0-5408
  9. AXP 1E 1547.0-5408: Swift/UVOT Upper Limits
  10. AXP 1E1547.0-5408 (SGR 1550-5418): Fermi GBM detection
  11. SGR 1550-5418 = AXP 1E1547.0-5408 (Trigger 330353)
  12. Swift discovery of a new Soft Gamma Repeater SGR 1550-5418
  13. Trigger 330353: Swift detection of a Galactic short soft burst
  14. SGR 0501+4516: preliminary results of the Suzaku ToO observation
  15. SGR 0501+4516 : P200 i-band observations
  16. SGR J0501+4516: radio pulsar searches with GBT and WSRT
  17. Recent VLA non-detection of SGR 0501+4516
  18. SGR 0501+4516: Spin Down Rate and Inferred Dipole Magnetic Field
  19. SGR 0501+4516: preliminary results of the first XMM-Newton observation
  20. nIR observations of SGR 0501+4516
  21. INTEGRAL ToO observation of SGR0501+4516
  22. SGR 0501+4516: Confirmation of the NIR counterpart
  23. SGR 0501+4516: Detection of possible optical counterpart
  24. SGR 0501+4516: WHT observations of the possible near-infrared counterpart
  25. VLA non-detection of SGR 0501+4516
  26. Radio Detection of SGR 0501+4516: Retraction
  27. SGR 0501+4516: XMM-Newton monitoring schedule
  28. SGR 0501+4516: Decline in Activity
  29. SGR 0501+4516: Proximity to supernova remnant HB9
  30. Enhanced Swift-XRT position of SGR 0501+4516
  31. SGR 0501+4516: GMRT Radio Observation at 618 MHz
  32. SGR 0501+4516: Swift XRT measure of the spin period
  33. SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
  34. Soft Gamma Repeater SGR 0501+4516: GBM Detection of multiple bursts
  35. Suzaku ToO Observation of SGR 0501+4516
  36. SGR 0501+4516: radio pulsar searches with GBT and WSRT
  37. Konus-Wind observations of new SGR 0501+4516
  38. INTEGRAL ToO Observation of SGR0501+4516
  39. Radio Detection of SGR 0501+4516
  40. SGR 0501+4516: MDM Optical Observations
  41. SGR 0501+4516: Astrotel-Caucasus optical observations
  42. SGR 0501+4516: UKIRT detection of possible infra-red counterpart
  43. SGR 0501+4516: WSRT Radio Observations
  44. Trigger 321551: Continued Large Flaring of SGR 0501+4516
  45. SGR 0501+4516: optical observations
  46. Swift Trigger 321481: A Large Flare from SGR 0501+4516
  47. SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
  48. Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
  49. GRB080818B: GLAST Burst Monitor detection
  50. Third event from SGR 0501+4516
  51. GRB 080822 (SGR 0501+4516): archival optical observations
  52. New Soft Gamma Repeater 0501+4516 was GRB 080822
  53. SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
  54. Konus-Wind observation of reactivation of SGR 1627-41
  55. Reactivation of SGR 1627-41
  56. GRB 080520: Swift XRT Refined Analysis
  57. GRB 080205: Swift XRT refined analysis
  58. GRB 080121: Upper limit on X-ray afterglow
  59. GRB080120: Swift XRT position
  60. Disregard the "GRB 071126" position
  61. Swift XRT follow-up observations of GRB071008
  62. GRB 071017: a SHORT GRB detected by INTEGRAL
  63. GRB 071003: XRT refined analysis
  64. INTEGRAL ToO observations of SGR1806-20
  65. SGR1806-20: Swift-BAT detection of enhanced activity
  66. Intense burst from SGR 1806-20 detected on September 7
  67. Swift detection of a outburst from SAX J1810.8-2609
  68. AGILE-ACS position for the SGR 1806-20 July 27 burst
  69. Intense burst from SGR 1806-20 detected on July 27
  70. GRB 070729: Swift-XRT refined analysis
  71. GRB 070520B: Swift-XRT refined analysis
  72. GRB 070520A: Swift-XRT refined analysis
  73. Suzaku ToO observation of SGR 1806-20
  74. INTEGRAL ToO Observation of SGR1806-20
  75. long burst from SGR 1806-20 detected on March 26
  76. GRB 070201: clarification on localization and Konus-Wind spectra
  77. IPN localization of very intense short GRB 070201
  78. GRB070107: Swift/XRT refined analysis
  79. GRB061222B: Swift-XRT Refined Analysis
  80. GRB061025: Swift XRT refined analysis
  81. IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
  82. GRB 060729: An update on the late-time Swift observations
  83. GRB 060926: Swift XRT refined analysis
  84. Two bright bursts from SGR 1806-20 detected with IBAS
  85. Image of the dust-scattering halo around SGR 1806-20
  86. Second VLA limit on new radio point source in SGR 1806-20
  87. A dust-scattering halo detected around SGR 1806-20
  88. VLA Upper Limit on Outburst of SGR 1806-20
  89. GRB060806 is similar to previous activity of SGR1806-20
  90. BAT Trigger #214277 is SGR 1900+14
  91. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  92. SGR 1900+14: Swift detection of an outburst
  93. SGR 1900+14: BAT observations
  94. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  95. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  96. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  97. SGR 1900+14: Swift-BAT detection of a bright outburst
  98. SGR 1900+14: CORRECTION to GCN 4923
  99. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  100. SGR 1900+14: Swift detection of renewed activity

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