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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"

19221 results found.

  1. UVOT observations of GRB070330
  2. GRB 070330: TAROT La Silla observatory optical observations
  3. GRB 070330 - Watcher Observations
  4. Konus-Wind observation of GRB 070328
  5. GRB 070328: Swift/UVOT Upper Limits
  6. long burst from SGR 1806-20 detected on March 26
  7. GRB 070328 : Suzaku ToO follow up starts
  8. GRB 070328, Swift-BAT refined analysis
  9. GRB 070328: Swift detection of a burst
  10. GRB 070311, deep optical photometry
  11. Short-Hard GRB 070209: PROMPT Observations
  12. GRB 070318: absorption-line redshift
  13. GRB070318: Swift UVOT continuing observations
  14. GRB 070318: Swift detection of a burst with an optical afterglow
  15. VLA observation of GRB 070311
  16. GRB 070311: Optical observation.
  17. GRB 070306: possible emission-line redshift
  18. GRB 070311: SARA upper limit
  19. GRB 070309: variability of the XRT afterglow candidate
  20. GRB070311: FRAM early follow-up limit
  21. GRB 070311: P60 Observations
  22. GRB 070311: Swift/UVOT Upper Limits
  23. GRB 070311: MITSuME Okayama Optical Observation
  24. GRB 070311: PAIRITEL confirmation of variability of REM candidate
  25. GRB 070311: REM candidate afterglow
  26. GRB060901: Candidate optical afterglow
  27. GRB070309: Swift/XRT possible afterglow detection
  28. GRB 070125: Chandra X-ray Confirmation of Jet Break
  29. GRB 070309: Swift/UVOT Upper Limits
  30. GRB 070306, optical observation
  31. Swift UVOT Finding Charts for GRB 070309
  32. VLA observation of GRB 070306
  33. GRB 070306: NOT observations
  34. GRB 070306 Swift/UVOT refined analysis
  35. GRB 070306: IR observations and candidate afterglow
  36. GRB 070306: Optical and IR observations with KANATA
  37. GRB070306 - SDSS Pre-burst Observations
  38. GRB 070306: Swift detection of a burst
  39. GRB 060605 new redshift
  40. GRB 070125, deep late-time optical observation
  41. VLA observation of GRB 070224
  42. GRB 070227: Swift/UVOT Upper Limits
  43. GRB 070227: TAROT La Silla observatory optical observations
  44. GRB 070227: Swift detection of a burst in ground analysis
  45. GRB 070224: Swift/UVOT Upper Limits
  46. VLA observation of GRB 070223
  47. VLA observation of GRB 070220
  48. GRB070224: Magellan Imaging Observations
  49. GRB 070224: WHT K-band imaging
  50. GRB 070224: MDM Observations
  51. GRB070224: Gemini Imaging Observations
  52. GRB 070224: SARA upper limit
  53. GRB 070224: optical afterglow candidate
  54. GRB 070224: MASTER-Net refind analysis
  55. GRB 070224: MASTER-VWF-Kislovodsk observations
  56. GRB 070224: Swift detection of a burst
  57. GRB 070223: Optical observations
  58. RHESSI Spectrum of GRB070220
  59. GRB070223: Swift/UVOT refined analysis
  60. GRB 070223: Optical-IR observation with KANATA
  61. GRB070223: MASTER-VWF-Kislovodsk observations
  62. GRB070223 - SDSS Pre-Burst Observations
  63. GRB070223: Swift burst
  64. Konus-Wind and Konus-A observations of GRB 070220
  65. GRB 070220: MITSuME Okayama Optical Observation
  66. GRB 070220 Swift-BAT Refined Analysis
  67. Swift/UVOT refined analysis of GRB070220
  68. GRB 070209: Swift XRT refined analysis
  69. GRB 070220: Observation with the KANATA 1.5m telescope
  70. GRB 070219: Gemini Observations
  71. GRB 070220: Swift detection of a burst
  72. GRB070219: MASTER-VWF-Kislovodsk observations
  73. GRB 070219: Swift/UVOT Upper limits
  74. GRB 070219: I-band observations
  75. GRB 070219: optical TNG observations
  76. GRB 070219: ROTSE-III Optical Limits
  77. GRB070219 - SDSS Pre-Burst Observations
  78. GRB 070219: Swift detection of a burst
  79. GRB 070125 observations with the GMRT
  80. GRB 070129: MDM I-band Detection
  81. GRB 070209: Swift XRT analysis
  82. GRB 070201: clarification on localization and Konus-Wind spectra
  83. IPN localization of very intense short GRB 070201
  84. GRB 070208: RAPTOR detection of early afterglow onset
  85. GRB 070208, Swift-BAT refined analysis
  86. GRB070208 - SDSS Pre-Burst Observations
  87. GRB 070208: Afterglow confirmation from P60
  88. GRB 070208: ROTSE-III Optical Limits
  89. GRB 070208: Swift detection of a burst
  90. GRB 070125 detection with CARMA
  91. GRB 070129: afterglow confirmation
  92. GRB070124: Swift-XRT Follow-up Observation
  93. GRB070126: Swift-XRT Observation
  94. GRB 070125: further AAVSO optical observations
  95. GRB 070129: Swift/UVOT Upper limits
  96. GRB 070129: Xinglong TNT optical Upper Limit
  97. GRB 070129: Swift-XRT Refined Analysis
  98. GRB 070129: VLT observations
  99. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  100. GRB 070129: Swift detection of a burst

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