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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32719 results found.

  1. GRB041218, BVRcIc field calibration
  2. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  3. GRB 041217: PROMPT Observations
  4. GRB041218: optical observations
  5. GRB041217: optical limit 30 min after GRB
  6. GRB 041218; optical candidate
  7. GRB 041218: Optical observations
  8. GRB 041217: LCO40 Optical Observations and Possible Candidates
  9. GRB041217: Optical Observations
  10. GRB041217: NIR and optical observations with REM
  11. GRB041217: Infrared Observations
  12. GRB041217: The First GRB Located On-Board Swift
  13. GRB041211: Faulkes Telescope continued optical monitoring
  14. Optical Transient in Lynx not a GRB
  15. Optical transient (GRB?) in Lynx
  16. GRB041211: Continued P60 Observations
  17. GRB041211, Faulkes Telescope optical observation
  18. GRB041211, BVRcIc field calibration
  19. GRB 041211: Infrared Observations
  20. GRB 041211: Optical follow-up in East Asian region
  21. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  22. GRB041015: Near-Infrared observations
  23. GRB 040924: Afterglow Color
  24. GRB 041006: GETS Optical Afterglow Observation
  25. Summary of the recent bursts from SGR 1806-20
  26. GRB 041006: Optical Observations
  27. GRB041006, late-time optical photometry
  28. GRB041006: RTT150 Optical Observations
  29. GRB041015 : Multi epoch optical observations
  30. GRB041006: RTT150 Optical Observations
  31. GRB 041016: Optical limits
  32. GRB 041015: Optical Observations at Rikubetsu
  33. GRB041006: Near Infrared observations
  34. GRB040924, BVRcIc field calibration
  35. GRB 041015: Optical limit at Osaka University
  36. GRB041015 : Optical follow-up at Kiso
  37. GRB 041006 R observations in Loiano
  38. GRB041006: VLT observations of the afterglow and host galaxy
  39. GRB041006: Optical observations and Potential host galaxy
  40. GRB041006, BVRcIc field calibration
  41. GRB 040924: VLT spectroscopy
  42. GRB 041006: SARA afterglow observations
  43. GRB041006, optical observation in CrAO
  44. Search for SN light in XRF 040912 with MEGACAM
  45. GRB 040916: Afterglow Color at Early Times
  46. GRB 041006 Optical afterglow observations
  47. GRB 041006: BR observations with VATT
  48. GRB 041006: Redshift confirmed
  49. GRB041006: Liverpool Telescope optical observations
  50. GRB 041006: Colour measurement
  51. GRB041006: break in the light curve
  52. GRB 041006: Radio Observations
  53. GRB 041006 : optical follow-up observation at Lulin Observatory
  54. GRB 041006 : Optical follow-up observation at TAROT
  55. GRB041006: Optical photometry and spectroscopy at TNG
  56. GRB 041006: presice astrometry
  57. GRB041006 (= H3570): Chandra Observations In Progress
  58. GRB 041006 : optical observation at Bisei
  59. GRB041006, optical I observation
  60. GRB041006 (=HETE3570): optical observations
  61. ROTSE-IIIa Observations of GRB 041006
  62. GRB041006, optical observation
  63. GRB041006, submillimetre observations
  64. GRB041006: MASTER optical observations
  65. GRB 041006: Optical decay
  66. GRB 041006 (=H3570): An X-Ray Rich GRB Localized in Real Time by HETE
  67. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  68. GRB041006: Fading of optical afterglow candidate
  69. GRB 041006 : Optical follow-up observation at KISO
  70. GRB 041006: Finding chart
  71. GRB 041006: Optical afterglow candidate
  72. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  73. XRF 020903: Observations of the Host Galaxy (authors)
  74. XRF 020903: Observations of the Host Galaxy
  75. GRB 040924: Second Epoch WSRT Radio Observations
  76. radio observations, GRB 040924
  77. Konus-Wind and Helicon-Coronas-F observations of GRB040924
  78. GRB040924,optical observation
  79. GRB040924, RTT150 optical observation
  80. GRB040924,optical observation
  81. GRB 040924: detection of possible host galaxy by Subaru
  82. GRB040924, RTT150 optical observation
  83. GRB040924: KAIT observations
  84. GRB040924: Afterglow magnitude at t=17.5hr
  85. GRB 040924: WSRT Radio Observations
  86. GRB 040924: NIR finding chart
  87. GRB040924 : Optical candidate observations at Lulin observatory
  88. GRB040924 : Optical candidate observations at Lulin observatory
  89. GRB 040924: Subaru NIR observation
  90. GRB 040924: RTT150 optical observations
  91. GRB 040924, optical follow-up
  92. GRB040924: MASTER: OT decay
  93. IPN triangulation of GRB040924 (H3564)
  94. GRB 040924(=H3564): A Short, Bright GRB Localized in Real Time by HETE
  95. XRF 040912: Radio Observations
  96. XRF 040916: Radio Observations
  97. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  98. XRF040916: continuing decay of OT
  99. TAROT Observations of GRB 040916 (HETE #3558)
  100. GRB040912(=H3557): Candidate Optical Afterglow

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