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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.

Advanced Search Examples (click to copy):

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

23403 results found.

  1. GRB071010b: optical observation
  2. Swift XRT and UVOT observations of GRB071028B
  3. GRB071101: Optical and NIR upper limits by KANATA
  4. GRB0711101: Two new source from Xinglong TNT observation
  5. GRB 071101: TAROT Calern observatory optical observations
  6. GRB071101 LOAO B,V,R,I observation
  7. GRB 071101: a nearby galaxy
  8. GRB 071101: Swift detection of a burst
  9. GRB 071031: Swift/UVOT detection of afterglow
  10. GRB 071031: Swift-XRT Team refined analysis
  11. GRB 071020: MITSuME Akeno optical observations
  12. GRB 071031: REM NIR and Optical observation
  13. GRB 071031: Swift detection of a burst with an optical counterpart
  14. GRB 071028B Swift-BAT detection of a burst
  15. GRB071025: Optical+NIR observations
  16. GRB 071028: SARA observations of variable source
  17. Swift UVOT upper limits to GRB071028
  18. GRB071028: Xinglong EST V-band upper limit
  19. GRB 071028: Swift-XRT Team refined analysis
  20. GRB 071028: Swift detection of a burst
  21. GRB 071003: Infrared Photometry with Keck Adaptive Optics
  22. GRB071021: MARGE Optical Limits
  23. GRB071020, optical upper limit
  24. GRB 071025: SARA VRI upper limits
  25. GRB 071025 Milagro GeV/TeV Observations
  26. GRB071025: Optical Pre-imaging from Palomar
  27. Swift UVOT upper limits
  28. GRB071025: Xinglong TNT I-band upper limit
  29. GRB 071025: Swift-XRT Team refined analysis
  30. GRB 071025, Swift-BAT refined analysis
  31. GRB071021 : CFHT Ks-band observation
  32. GRB 071025a: PAIRITEL observations
  33. GRB 071025: Swift detection of a burst
  34. GRB 071021: R-band detection and analysis
  35. GRB071021: Optical+NIR observations
  36. Possible radio detection of GRB 071021 with the VLA
  37. GRB 071021: (Relatively shallow) IR non-detections; motivation for optical spectroscopy
  38. GRB 071020: SARA observations
  39. Radio detection of GRB 071020 with the VLA
  40. GRB071021: MITSuME Okayama Optical Upper Limits
  41. GRB 071021: Magellan i-band observation
  42. GRB 071021: Magellan R-band observation
  43. GRB 071021: Z-band detection
  44. GRB071018: 2nd epoch obsevations of Xinglong TNT
  45. GRB 071021: Xinglong TNT optical Upper Limit
  46. GRB 071021 : Lulin R-band limit
  47. GRB 071021: Swift detection of a burst
  48. GRB071020A: Xinglong TNT Optical afterglow observations
  49. GRB 071020, Swift-BAT refined analysis
  50. GRB 071020A: IR Imaging with PAIRITEL
  51. GRB071020 - SDSS Pre-burst Observations
  52. GRB 071020: Swift detection of a bright burst
  53. GRB 071018: Mercator Telescope optical observations
  54. Swift autonomous slewing re-enabled
  55. GRB 071018: SARA observations
  56. GRB 071018: Swift-XRT observation
  57. GRB 071017 - Swift XRT observations
  58. GRB 071018: Possible OT from Xinglong TNT observation
  59. GRB 071010A: Late-time Keck/LRIS photometry - possible host galaxy and jet break
  60. GRB 071018, Swift-BAT refined analysis
  61. GRB 071018?: Swift detection of a possible burst
  62. GRB 071013: 3rd TLS Epoch - constraints on variability
  63. GRB 071013: TLS 2nd epoch - Kornienko candidate constant
  64. GRB071013: optical observations
  65. GRB 071011: MITSuME Optical Observations
  66. GRB 070920A: deep optical observations at the NOT
  67. GRB 071010B: Keck/LRIS Photometry
  68. GRB 071013: TLS Upper Limit
  69. VLA non-detection of GRB 071011
  70. GRB 071013: Optical observations
  71. GRB 071013: optical observations at NOT
  72. GRB071010B, BVRcIc field calibration
  73. GRB 20071013: Xinglong TNT optical Upper Limit
  74. GRB 071013: Swift detection of a burst
  75. GRB 071010C Swift-BAT detection of a burst
  76. GRB 071011: Optical Limit after 13.95hrs
  77. GRB 071010B correction to GCN 6892 optical observations
  78. GRB 071011: Swift-XRT refined analysis
  79. VLA non-detection of GRB 071010A
  80. GRB 071011: NAYUTA Optical Observation, correction to GCN6886
  81. GRB 071011: Confirmation of P60 optical afterglow
  82. GRB 071010B: Optical Detection
  83. GRB 071011: Kanazawa Optical limits
  84. GRB 071011: P60 Optical Afterglow Candidate
  85. GRB 071011: MARGE Optical Limits
  86. GRB 071010B: Super-LOTIS upper limit
  87. GRB 071010B optical photometry
  88. GRB 071011: XRT afterglow detection
  89. GRB 071011: Early Super-LOTIS Observations
  90. GRB 071011: NAYUTA Optical Observation
  91. GRB 071010A: Continued Keck Imaging
  92. GRB 071010B: Bright OT confirmed with TLS
  93. GRB 071011: Swift detection of a burst
  94. Optical Observation: GRB 071010
  95. Optical observations: GRB 071010A
  96. GRB071010B: Swift/XRT detection
  97. GRB 071006, Swift-BAT refined analysis
  98. GRB071008: optical observations
  99. GRB 071010A: Keck/LRIS Photometry
  100. GRB 071010B: Swift detection of a burst

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