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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"

36180 results found.

  1. GRB 070125: further AAVSO optical observations
  2. GRB 070125: MITSuME Okayama optical observation
  3. Konus-Wind observation of GRB 070125
  4. GRB 070125: AAVSO optical observations
  5. GRB 070125: optical observations
  6. GRB 070126: VLT observations
  7. GRB070126: Swift-XRT possible detection of an afterglow
  8. GRB 070125: PROMPT detections
  9. GRB 070124: Suzaku WAM observation of the prompt emissions
  10. GRB 070125: WSRT Radio Observations
  11. GRB 070125: UVOT Detection in Ultraviolet Filters
  12. GRB 070126, Swift-BAT refined analysis of a very faint burst
  13. GRB070125: Optical observation by Kanata
  14. Possible GRB 070126: Swift/UVOT Upper Limit
  15. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  16. GRB 070125: Xinglong TNT optical observations
  17. GRB 070125: Continued P60 Observations
  18. GRB 070125: pseudo-z~1.5 from spectral parameters of the prompt emission
  19. GRB 070125: Keck/LRIS Spectroscopy -- Evidence for a very low redshift
  20. GRB 070125: Lick 3m Spectroscopy
  21. GRB070125: Swift-XRT Refined Analysis
  22. GRB 070125: SARA detection in R
  23. GRB 070125: P60 Optical Afterglow Candidate
  24. GRB 070126?: Swift detection of a possible burst
  25. GRB070125 redshift request
  26. RHESSI Spectrum of GRB070125
  27. IPN-BAT localization of GRB070125 (very long duration, intense)
  28. Konus-Wind observation of short hard GRB 070124
  29. IPN localization of GRB070124 (short duration, hard spectrum)
  30. GRB 070110: optical break
  31. GRB 070110: Continued Detection and Request for Ground Followup
  32. GRB 050904: Second Epoch of HST/NICMOS Observations
  33. GRB 070110: Ep,i - Eiso correlation
  34. GRB 070107: Suzaku WAM observation of the prompt emission
  35. GRB 070110: VLT R-band photometry
  36. GRB 070110 declared a "Burst of Interest" by Swift team
  37. Further Retractions of previous Swift-BAT triggers
  38. Swift-BAT Trigger 255685 is not a GRB
  39. Trigger 255685: Swift detection of a possible burst
  40. GRB 070110: VLT absorption redshift
  41. GRB 070110: UVOT Observations of a Candidate Afterglow
  42. GRB 070110, Swift-BAT refined analysis
  43. GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
  44. GRB 070110: Swift detection of a burst with a possible optical afterglow
  45. IBAS Alert n. 4047: Not a GRB
  46. GRB070107: Swift/XRT refined analysis
  47. GRB 070107: Possible UVOT Afterglow
  48. GRB 070107, Swift-BAT refined analysis
  49. GRB 070107: Swift/XRT position
  50. GRB 070107: Swift detection of a burst
  51. VLA observation of GRB 061222B
  52. VLA detection of GRB 061222A
  53. GRB 061201: Nearby Galaxy Cluster Abell 995 is at z=0.0865
  54. GRB070103: KPNO 4m+FLAMINGOS J limit
  55. GRB 070103: Swift/UVOT Upper limits
  56. GRB 070103, Swift-BAT refined analysis
  57. GRB 070103: NOT observations
  58. GRB 070103: TAROT Calern observatory optical observations
  59. GRB 070103: Swift detection of a burst
  60. Retractions of previous Swift-BAT triggers
  61. GRB061222a: optical observations
  62. erratum : SDSS Pre-burst Observations of GRB061126
  63. Konus-Wind observation of GRB 061222A
  64. GRB 061210: Swift/XRT Astrometry Correction
  65. GRB 050826: MDM Redshift
  66. GRB 061222B: TAROT La Silla observatory early optical observations
  67. GRB 061218: TAROT La Silla observatory early optical observations
  68. GRB 061222A: MITSuME Akeno optical upper limits
  69. GRB 061222A: Confirmation of Gemini Afterglow Candidate
  70. GRB 061222B: MITSuME Akeno optical upper limits
  71. GRB 061222A: Xinglong Optical Limit
  72. GRB 061222A: Gemini Afterglow Candidate
  73. GRB 061222B, Swift-BAT refined analysis
  74. GRB061222A Swift/UVOT: Upper Limits
  75. GRB 061222B: Swift/UVOT Upper limits
  76. GRB 061222B: Observation with the KANATA 1.5m telescope
  77. GRB061222B: Swift-XRT Refined Analysis
  78. GRB 061222A: Observation with the KANATA 1.5m telescope
  79. GRB 061222B: BOOTES-IR optical observations
  80. GRB 061222B: SARA upper limit
  81. GRB 061222A: Swift-XRT refined analysis
  82. GRB 061217: Magellan host galaxy redshift
  83. GRB 061222A, Swift-BAT refined analysis
  84. GRB 061222B: REM NIR/optical observations
  85. GRB 061222b: Refined redshift
  86. GRB 061222b, SMARTS optical/IR afterglow observations
  87. GRB 061222B: TAROT La Silla observatory afterglow observation
  88. GRB 061222B: TAROT La Silla observatory optical observations
  89. GRB 061222b: Magellan redshift
  90. GRB 061222B: Swift detection of a burst
  91. GRB 061222b: optical afterglow
  92. GRB 061222A: Prompt ROTSE-III Optical Limits
  93. GRB 061222: Swift detection of a burst
  94. GRB 061217: Astrometry-Corrected XRT Position
  95. GRB 061201: Magellan redshift of nearby galaxy
  96. GRB 061217: Confirmation of host candidate
  97. GRB 061217: Object ib GCN 5948 is a star
  98. GRB 061217: Extended object in the revised XRT error circle
  99. GRB 061217, Candidate host galaxy
  100. GRB 061217 - Swift/XRT position correction

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