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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"

24603 results found.

  1. GRB020406(?), optical observations
  2. GRB 020405: Decay index
  3. Short RXTE/ASM transient 020406; may be a GRB
  4. GRB020405, Radio Observations
  5. GRB 020405, U-band observations
  6. GRB011212: Optical Observations
  7. GRB 020331: NIR Observations
  8. GRB020331 NIR observation at KPNO (re-submission)
  9. GRB02033 NIR observation at KPNO
  10. GRB020331 field photometry
  11. GRB 020331, NIR observations
  12. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  13. GRB 020322: BeppoSAX observations of the X-ray afterglow
  14. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  15. Near-Infrared Observations of GRB020322 at TIRGO
  16. GRB 020321, Radio Observations
  17. GRB 020322: Optical Observations
  18. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  19. GRB 020321: Optical observations
  20. GRB020317 BVRI field photometry
  21. GRB011211 revised BVRI field photometry
  22. GRB020305 BVRI field photometry
  23. GRB020322 BVRI field photometry
  24. GRB 020322: Optical Sources and Improved Astrometry
  25. GRB020317: optical observations
  26. GRB020321 optical observations
  27. GRB020321: a faint BeppoSAX detection
  28. GRB 020317 : KISO Optical Observations
  29. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  30. GRB 020305: Optical Observations
  31. GRB020317, optical observations
  32. GRB 020317: Optical observations
  33. GRB 011121: Third HST Epoch
  34. GRB020305: Properties of the Candidate Optical Afterglow
  35. GRB 011121: HST Observations reveal an intermediate-time multicolor
  36. GRB011130 (XRF011130) Second Epoch Chandra Observations
  37. GRB020305: Subaru Optical Observations
  38. XRF/GRB 011030: Detection of the Probable Host Galaxy
  39. GRB 020305: Candidate optical afterglow
  40. GRB020305, optical observations
  41. IPN triangulation of GRB020305 (HETE 1939)
  42. GRB020305 (=H1939): Localization of a GRB by HETE
  43. HST Imaging of the afterglow and host of GRB 011121
  44. IPN detection and localization of Cygnus X-1 flares
  45. SGR1900+14 activity
  46. IPN Upper Limits to a GRB Associated With SN2002ap
  47. GRB020124 BVRI field photometry
  48. GRB020127: Comparison of Chandra Epochs and Identification of Possible Counterparts
  49. SN2002ap (SN/GRB?) Echelle spectra
  50. GRB020127 Optical Observations
  51. SN 2002ap in M74
  52. SN2002ap (SN/GRB?) UBVRI Field Photometry
  53. GRB020127: Chandra Observations and Prospective Counterparts
  54. pre-SN2002ap (SN/GRB?) imaging of M74
  55. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  56. GRB020124, optical observations
  57. GRB 020127, I-band observations starting 3.14-hr after the event
  58. GRB010921 Optical Observations
  59. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  60. GRB020124: Optical observations
  61. GRB 020124: Optical observations
  62. GRB 020124: Optical afterglow
  63. GRB020124(=H1896): Localization of a Long GRB by HETE
  64. Possible optical counterpart to a GRB
  65. GRB011212, Optical Observations
  66. Optical polarization observations for GRB011211
  67. GRB 011211: Detection of the Probable Host Galaxy
  68. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  69. GRB 011130: Optical Observations of X-ray and Radio Sources
  70. GRB 011212: optical observation at Asiago
  71. GRB 011211: Evidence for an Optical Break
  72. GRB 011211: TNG Spectroscopic Observations
  73. optical follow-up of GRB(XRF) 011211
  74. GRB 011212: optical observation at Oslo (relayed)
  75. GRB 011211, Optical Observations
  76. GRB011212, BVRI field photometry
  77. GRB011211, BVRI field photometry
  78. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  79. Fading of the optical source associated of XRF 011211
  80. GRB 011211 Optical Observations: Likely Afterglow
  81. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  82. GRB011130 (XRF011130) Chandra Observations
  83. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  84. GRB 011130, K band observations
  85. GRB011130, optical observations
  86. GRB011130 (=XRF011130): Second Revised Localization by HETE
  87. GRB011130 (XRF011130) SDSS PT i-band observations
  88. XRF011130: Infrared Observations
  89. GRB 011121
  90. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  91. GRB 011121: J-band observations
  92. GRB 011121: NIR observations, host galaxy?
  93. GRB011121: UBRI Observations
  94. GRB 011121 J-Band Astrometry
  95. GRB 011121: Detection of Bright IR Counterpart
  96. GRB011121: possible redshift, continued decay
  97. GRB 011030: TNG K-band observation
  98. XRF011030: J and K band observations
  99. XRF011030: Chandra Observations
  100. GRB011030: Z-band observations

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