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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"

20354 results found.

  1. GRB020531: Observations with the Chandra X-ray Observatory
  2. IPN triangulation of GRB020603 (possible short/hard GRB)
  3. GRB020531, optical observations
  4. GRB020531: optical observations
  5. GRB020531(=H2042): Optical Observations
  6. GRB020531(=H2042): Optical Observations
  7. GRB020525, optical observations
  8. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  9. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  10. GRB020405 field photometry at ESO
  11. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  12. GRB020321 : Optical observations.
  13. XRF 020427
  14. The end of BSAX GRB activities
  15. GRB 020410, Radio Observations
  16. GRB 020124: Optical observations
  17. IPN triangulation of GRB020418
  18. GRB020405: VLT observations of the OT environment
  19. IPN triangulation of GRB020413
  20. GRB 020409: No Evidence for an Optical Afterglow
  21. GRB 020331 Kyoto observation on March 31
  22. GRB 020409: Optical observations
  23. X-ray afterglow of GRB020321
  24. GRB020331 optical observations with RIMOTS
  25. GRB020124 optical observations with RIBOTS/RIMOTS
  26. GRB 020321: Candidate X-ray Counterparts
  27. GRB020406(?), optical observations
  28. GRB020405, Radio Observations
  29. GRB 020405, U-band observations
  30. GRB011212: Optical Observations
  31. GRB020331 NIR observation at KPNO (re-submission)
  32. GRB02033 NIR observation at KPNO
  33. GRB020331 field photometry
  34. GRB 020331, NIR observations
  35. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  36. GRB 020322: BeppoSAX observations of the X-ray afterglow
  37. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  38. Near-Infrared Observations of GRB020322 at TIRGO
  39. GRB 020322: Optical Observations
  40. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  41. GRB 020321: Optical observations
  42. GRB020317 BVRI field photometry
  43. GRB011211 revised BVRI field photometry
  44. GRB020305 BVRI field photometry
  45. GRB020322 BVRI field photometry
  46. GRB020317 : Near IR Observations from Mt Abu Observatory
  47. GRB 020322: Optical Sources and Improved Astrometry
  48. GRB 011121: Fourth Epoch of HST Imaging
  49. GRB020317: optical observations
  50. GRB020321 optical observations
  51. GRB020321: a faint BeppoSAX detection
  52. GRB 020317 : KISO Optical Observations
  53. GRB 020305: Optical Observations
  54. GRB020317, optical observations
  55. GRB 020317: Optical observations
  56. GRB020305: Properties of the Candidate Optical Afterglow
  57. GRB 011121: HST Observations reveal an intermediate-time multicolor
  58. GRB011121, possible supernova association
  59. GRB011130 (XRF011130) Second Epoch Chandra Observations
  60. XRF/GRB 011030: Detection of the Probable Host Galaxy
  61. GRB020305, optical observations
  62. HST Imaging of the afterglow and host of GRB 011121
  63. GRB 010921: HST Observations
  64. IPN detection and localization of Cygnus X-1 flares
  65. SGR1900+14 activity
  66. IPN/HETE Detection of Bursts from SGR1900+14
  67. IPN Upper Limits to a GRB Associated With SN2002ap
  68. GRB020124 BVRI field photometry
  69. GRB020127: Palomar and VLA Observations of Possible Counterparts
  70. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  71. SN2002ap (SN/GRB?) Echelle spectra
  72. GRB020127 Optical Observations
  73. SN2002ap (SN/GRB?) UBVRI Field Photometry
  74. GRB020127: Chandra Observations and Prospective Counterparts
  75. pre-SN2002ap (SN/GRB?) imaging of M74
  76. GRB020124, optical observations
  77. GRB020127: Optical observations
  78. GRB 020127, I-band observations starting 3.14-hr after the event
  79. GRB010921 Optical Observations
  80. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  81. GRB020124: Optical observations
  82. GRB 020124: Optical observations
  83. Possible optical counterpart to a GRB
  84. GRB011212, Optical Observations
  85. Optical polarization observations for GRB011211
  86. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  87. GRB 011130: Optical Observations of X-ray and Radio Sources
  88. GRB 011130, Radio/X-ray Comparison
  89. GRB 011212: optical observation at Asiago
  90. GRB 011211: Evidence for an Optical Break
  91. GRB 011212: optical observation at Oslo (relayed)
  92. GRB 011211, Optical Observations
  93. GRB011212, BVRI field photometry
  94. GRB011211, BVRI field photometry
  95. Fading of the optical source associated of XRF 011211
  96. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  97. GRB011130 (XRF011130) Chandra Observations
  98. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  99. GRB 011130: Magellan spectroscopy
  100. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418

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