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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"

23410 results found.

  1. GRB020321 : Optical observations.
  2. XRF 020427
  3. GRB 020124: Optical observations
  4. GRB 020418: Optical observations
  5. IPN triangulation of GRB020418
  6. GRB020405: VLT observations of the OT environment
  7. IPN triangulation of GRB020413
  8. GRB 020409: No Evidence for an Optical Afterglow
  9. GRB 020331 Kyoto observation on March 31
  10. X-ray afterglow of GRB020321
  11. GRB020405: VLT optical observations and V band decay slope
  12. GRB020331 optical observations with RIMOTS
  13. GRB020124 optical observations with RIBOTS/RIMOTS
  14. GRB 020321: Candidate X-ray Counterparts
  15. ASM GRB candidate 020406 refined error box
  16. GRB020406(?), optical observations
  17. GRB020405: VLT optical observations
  18. GRB020405, Radio Observations
  19. GRB 020405, U-band observations
  20. IPN localization of GRB020405
  21. GRB011212: Optical Observations
  22. GRB020331 NIR observation at KPNO (re-submission)
  23. GRB02033 NIR observation at KPNO
  24. GRB020331 field photometry
  25. GRB 020331 Optical Observations
  26. GRB 020331, NIR observations
  27. GRB 020321: Infrared observations
  28. GRB 020322: BeppoSAX observations of the X-ray afterglow
  29. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  30. GRB 020322, Radio observations
  31. Near-Infrared Observations of GRB020322 at TIRGO
  32. GRB 020322: Optical Observations
  33. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  34. GRB 020321: Optical observations
  35. GRB020317 BVRI field photometry
  36. GRB011211 revised BVRI field photometry
  37. GRB020305 BVRI field photometry
  38. GRB020322 BVRI field photometry
  39. GRB020317 : Near IR Observations from Mt Abu Observatory
  40. GRB 020322: Optical Sources and Improved Astrometry
  41. Bepposax GRB020322 The second springtime BSAX GRB
  42. GRB020317: optical observations
  43. GRB020321 optical observations
  44. GRB020321: a faint BeppoSAX detection
  45. GRB 020317 : KISO Optical Observations
  46. GRB 020305: Optical Observations
  47. GRB020317, optical observations
  48. GRB 020317: Optical observations
  49. GRB 011121: Third HST Epoch
  50. GRB020305: Properties of the Candidate Optical Afterglow
  51. GRB 011121: HST Observations reveal an intermediate-time multicolor
  52. GRB011130 (XRF011130) Second Epoch Chandra Observations
  53. XRF/GRB 011030: Detection of the Probable Host Galaxy
  54. GRB020305, optical observations
  55. IPN triangulation of GRB020305 (HETE 1939)
  56. GRB020305 (=H1939): Localization of a GRB by HETE
  57. HST Imaging of the afterglow and host of GRB 011121
  58. GRB020127: Further VLA Observations of Possible Counterparts
  59. SGR1900+14 activity
  60. IPN Upper Limits to a GRB Associated With SN2002ap
  61. GRB020124 BVRI field photometry
  62. GRB020127: Palomar and VLA Observations of Possible Counterparts
  63. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  64. SN2002ap (SN/GRB?) Echelle spectra
  65. GRB020127, WSRT radio observations
  66. GRB020127 Optical Observations
  67. SN 2002ap in M74
  68. SN2002ap (SN/GRB?) UBVRI Field Photometry
  69. GRB020127: Chandra Observations and Prospective Counterparts
  70. pre-SN2002ap (SN/GRB?) imaging of M74
  71. GRB020124, optical observations
  72. GRB020127: Optical observations
  73. GRB 020127, I-band observations starting 3.14-hr after the event
  74. IPN triangulation of GRB020127 (=H1902)
  75. GRB010921 Optical Observations
  76. GRB020124: Optical observations
  77. GRB 020124: Optical observations
  78. IPN triangulation of GRB020124 (HETE 1896)
  79. GRB020124(=H1896): Localization of a Long GRB by HETE
  80. Possible optical counterpart to a GRB
  81. GRB011212, Optical Observations
  82. Optical polarization observations for GRB011211
  83. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  84. GRB 011130: Optical Observations of X-ray and Radio Sources
  85. GRB 011130, Radio/X-ray Comparison
  86. GRB 011212: optical observation at Asiago
  87. GRB 011211: Evidence for an Optical Break
  88. GRB 011212: optical observation at Oslo (relayed)
  89. GRB 011211, Optical Observations
  90. GRB011212, BVRI field photometry
  91. GRB011211, BVRI field photometry
  92. Fading of the optical source associated of XRF 011211
  93. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  94. GRB011130 (XRF011130) Chandra Observations
  95. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  96. GRB 011130, K band observations
  97. GRB011130, optical observations
  98. GRB011130 (XRF011130) SDSS PT i-band observations
  99. XRF011130: Infrared Observations
  100. GRB011130 (=XRF011130), Optical Observations

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