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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"

28051 results found.

  1. GRB 020625: Optical observations
  2. GRB 020531: optical photometry of Chandra sources
  3. GRB020625 (=H2081): A Long Burst Localized by HETE
  4. The Probable Host Galaxy of GRB/XRF 020427
  5. GRB/XRF 020427, detection of an underlying system with the VLT
  6. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  7. AXP 1E2259+586 optical observations
  8. Fading Optical Source in the Field of GRB020531
  9. GRB 020531, INT+WFC deep optical upper limits
  10. SGR-like Bursts from the AXP 1E 2259+586
  11. GRB020405: polarimetric observations
  12. GRB 020531, simultaneous optical observations
  13. GRB 020531/Candidate Redshift
  14. GRB020531: Detection of Candidate Host Galaxy
  15. GRB020531: Second epoch Chandra observations
  16. GRB020604, optical observations
  17. GRB020604, BVRcIc field photometry
  18. GRB020603, BVRcIc field observations
  19. GRB020531, BVRcIc field photometry
  20. GRB020531 Optical Observations
  21. GRB020531: Observations with the Chandra X-ray Observatory
  22. GRB020531, optical observations
  23. GRB020531: optical observations
  24. GRB020531(=H2042): Optical Observations
  25. GRB020531(=H2042): Optical Observations
  26. GRB020531: Optical observations
  27. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  28. GRB020525, optical observations
  29. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  30. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  31. HST detection of the likely host galaxy of GRB 020124
  32. GRB020405 field photometry at ESO
  33. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  34. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  35. GRB020321 : Optical observations.
  36. XRF 020427
  37. GRB 020124: Optical observations
  38. IPN triangulation of GRB020418
  39. GRB020405: VLT observations of the OT environment
  40. IPN triangulation of GRB020413
  41. GRB020405: predicted break
  42. GRB 020409: No Evidence for an Optical Afterglow
  43. GRB 020331 Kyoto observation on March 31
  44. GRB020410: BeppoSAX NFI observation
  45. X-ray afterglow of GRB020321
  46. GRB020331 optical observations with RIMOTS
  47. GRB020124 optical observations with RIBOTS/RIMOTS
  48. GRB 020321: Candidate X-ray Counterparts
  49. GRB020406(?), optical observations
  50. GRB 020405: Decay index
  51. Short RXTE/ASM transient 020406; may be a GRB
  52. GRB020405, Radio Observations
  53. GRB 020405, U-band observations
  54. GRB011212: Optical Observations
  55. GRB 020331: NIR Observations
  56. GRB020331 NIR observation at KPNO (re-submission)
  57. GRB02033 NIR observation at KPNO
  58. GRB020331 field photometry
  59. GRB 020331, NIR observations
  60. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  61. GRB 020322: BeppoSAX observations of the X-ray afterglow
  62. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  63. Near-Infrared Observations of GRB020322 at TIRGO
  64. GRB 020321, Radio Observations
  65. GRB 020322: Optical Observations
  66. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  67. GRB 020321: Optical observations
  68. GRB020317 BVRI field photometry
  69. GRB011211 revised BVRI field photometry
  70. GRB020305 BVRI field photometry
  71. GRB020322 BVRI field photometry
  72. GRB 020322: Optical Sources and Improved Astrometry
  73. GRB020317: optical observations
  74. GRB020321 optical observations
  75. GRB020321: a faint BeppoSAX detection
  76. GRB 020317 : KISO Optical Observations
  77. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  78. GRB 020305: Optical Observations
  79. GRB020317, optical observations
  80. GRB 020317: Optical observations
  81. GRB 011121: Third HST Epoch
  82. GRB020305: Properties of the Candidate Optical Afterglow
  83. GRB 011121: HST Observations reveal an intermediate-time multicolor
  84. GRB011130 (XRF011130) Second Epoch Chandra Observations
  85. GRB020305: Subaru Optical Observations
  86. XRF/GRB 011030: Detection of the Probable Host Galaxy
  87. GRB 020305: Candidate optical afterglow
  88. GRB020305, optical observations
  89. IPN triangulation of GRB020305 (HETE 1939)
  90. GRB020305 (=H1939): Localization of a GRB by HETE
  91. HST Imaging of the afterglow and host of GRB 011121
  92. IPN detection and localization of Cygnus X-1 flares
  93. SGR1900+14 activity
  94. IPN Upper Limits to a GRB Associated With SN2002ap
  95. GRB020124 BVRI field photometry
  96. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  97. SN2002ap (SN/GRB?) Echelle spectra
  98. GRB020127 Optical Observations
  99. SN 2002ap in M74
  100. SN2002ap (SN/GRB?) UBVRI Field Photometry

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