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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').
Advanced Search

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"

26499 results found.

  1. GRB 070125: MITSuME Okayama optical observation
  2. GRB 070125: optical observations
  3. GRB 070126: VLT observations
  4. GRB 070124: Suzaku WAM observation of the prompt emissions
  5. GRB070125: Optical observation by Kanata
  6. GRB070124: Swift-XRT Observation
  7. Possible GRB 070126: Swift/UVOT Upper Limit
  8. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  9. GRB 070125: Xinglong TNT optical observations
  10. GRB 070125: Keck/LRIS Spectroscopy -- Evidence for a very low redshift
  11. GRB 070125: Lick 3m Spectroscopy
  12. GRB070125: Swift-XRT Refined Analysis
  13. GRB 070125: SARA detection in R
  14. GRB 070125: P60 Optical Afterglow Candidate
  15. GRB 070126?: Swift detection of a possible burst
  16. GRB070125 redshift request
  17. RHESSI Spectrum of GRB070125
  18. Konus-Wind observation of short hard GRB 070124
  19. IPN localization of GRB070124 (short duration, hard spectrum)
  20. GRB 070110: Continued Detection and Request for Ground Followup
  21. GRB 070110: Ep,i - Eiso correlation
  22. GRB 070110 declared a "Burst of Interest" by Swift team
  23. GRB070110: Swift XRT Team refined analysis
  24. GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
  25. GRB 070110: Swift detection of a burst with a possible optical afterglow
  26. GRB070107: Swift/XRT refined analysis
  27. GRB 070107, Swift-BAT refined analysis
  28. GRB 070107: Swift detection of a burst
  29. VLA observation of GRB 061222B
  30. VLA detection of GRB 061222A
  31. GRB070103: APO SPIcam i' and z' limits
  32. GRB 070103: Swift/UVOT Upper limits
  33. GRB070103: Swift XRT refined analysis
  34. GRB 070103: NOT observations
  35. GRB 070103: TAROT Calern observatory optical observations
  36. erratum : SDSS Pre-burst Observations of GRB061126
  37. Konus-Wind observation of GRB 061222A
  38. GRB 061210: Swift/XRT Astrometry Correction
  39. GRB 050826: MDM Redshift
  40. GRB 061222A: Confirmation of Gemini Afterglow Candidate
  41. GRB 061222A: Xinglong Optical Limit
  42. GRB 061222A: Gemini Afterglow Candidate
  43. GRB061222A Swift/UVOT: Upper Limits
  44. GRB 061222B: Swift/UVOT Upper limits
  45. GRB 061222B: Observation with the KANATA 1.5m telescope
  46. GRB061222B: Swift-XRT Refined Analysis
  47. GRB 061222A: Observation with the KANATA 1.5m telescope
  48. GRB 061222B: BOOTES-IR optical observations
  49. GRB 061222B: SARA upper limit
  50. GRB 061222A: Swift-XRT refined analysis
  51. GRB 061222B: REM NIR/optical observations
  52. GRB 061222B: TAROT La Silla observatory afterglow observation
  53. GRB 061222B: TAROT La Silla observatory optical observations
  54. GRB 061222B: Swift detection of a burst
  55. GRB 061222A: Prompt ROTSE-III Optical Limits
  56. GRB 061222: Swift detection of a burst
  57. GRB 061210: Possible Host Galaxy (S2-G2) Keck Spectrum
  58. GRB 061218: TAROT La Silla observatory optical observations
  59. GRB 061217: TAROT Calern observatory optical observations
  60. GRB 061218: TORTOREM optical upper limits
  61. GRB 061218, Swift-BAT refined analysis
  62. GRB061217: VLT NIR observations
  63. GRB 061218, SMARTS optical/IR observations
  64. GRB 061218: REM prompt observations
  65. Swift triggers (#251863) on a possible burst
  66. GRB 061217, SMARTS optical observations
  67. GRB061217: Swift/UVOT refined analysis.
  68. GRB 061217: optical observations at Calar Alto
  69. GRB061217 - Swift/XRT refined analysis
  70. GRB 061217: Magellan Observations
  71. GRB 061217: REM prompt observations
  72. GRB 061217: ROTSE-III Optical Limits
  73. GRB061210: Swift/UVOT observations
  74. GRB 061210: Swift XRT analysis - Possible counterparts
  75. GRB 061210 : Faulkes North Telescope optical limit
  76. GRB 061210: Gemini/GMOS Observations
  77. GRB 061126: Radio Observations
  78. GRB061210: Radio Observations
  79. Optical Afterglow observations of GRB 061126
  80. GRB 060926: MASTER: discovery of the optical flare
  81. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  82. GRB 061202: TORTOREM optical upper limits
  83. GRB 061201: VLT optical decay
  84. GRB 061201: SOAR Confirmation of Candidate Afterglow
  85. GRB 061202: Swift XRT refined analysis
  86. GRB061202: FRAM early follow-up limit
  87. GRB061202 optical limit by "Pi of the Sky"
  88. Konus-Wind observation of GRB 061201
  89. GRB061202: optical/NIR observations with REM
  90. GRB061202: Swift/UVOT Upper Limits
  91. GRB 061202: Swift detection of a burst
  92. GRB 061201: Swift XRT Team refined analysis
  93. GRB 061201: VLT optical observations
  94. GRB 061201, Swift-BAT refined analysis of the SHB
  95. GRB 061201: Swift detection of a short hard burst
  96. GRB 061121, SMARTS optical/IR observations
  97. INT+WFC observations of GRB 061126
  98. RHESSI Spectrum of GRB061126
  99. GRB061126: Optical afterglow observations from MIRO
  100. GRB061126: Optical afterglow observations from MIRO

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