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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"

21946 results found.

  1. GRB 050906: Optical observations at the Very Large Telescope
  2. GRB050904: CrAO optical observations
  3. GRB 050906: Swift-BAT refined analysis
  4. GRB 050906: Swift XRT upper limit
  5. GRB 050906: Radio Observations
  6. GRB050906: P60 Observations
  7. GRB 050904: more VLT NIR observations
  8. GRB 050904: Did SWIFT/XRT see the prompt GRB emission ?
  9. GRB 050906: Bright galaxy in BAT error box
  10. GRB 050904: More SOAR
  11. GRB 050904: Swift/UVOT observations
  12. GRB 050904: NIR object inside the XRT error box
  13. GRB 050904: SOAR YJ and PROMPT Ic Observations
  14. GRB050904: Optical Observations
  15. GRB 050904: Environmental Constraints
  16. GRB 050904: Possible High-Redshift GRB
  17. GRB 050904: SOAR/PROMPT Observations
  18. GRB050904: P60 Observations
  19. GRB 050824: MDM Observations
  20. GRB 050827 : OSN 1.5m optical observations
  21. GRB 050827: P200 NIR Observations
  22. GRB 050826 : Lulin R band observation
  23. GRB050820A: RTT150 optical observations
  24. GRB050827: RTT150 optical observations
  25. Subaru Observations of GRB050724
  26. GRB 050826: Optical Candidate
  27. GRB050826: Swift-BAT detection of a long burst
  28. GRB050824: MASTER final analysis of the OT observations
  29. Possible GRB050825:MASTER optical observations
  30. GRB050824: CORRECTION to UVOT observing times
  31. GRB050824: Swift/UVOT detection of fading afterglow
  32. GRB050824, I-band imaging
  33. GRB050824: Radio Observations
  34. GRB 050824 optical candidate
  35. GRB050820A: RTT150 optical observations
  36. GRB050820a: PROMPT RcIc Observations
  37. VLT/UVES spectroscopy of GRB050820
  38. GRB 050820A BAT observations of second, larger episode of emission
  39. GRB050813: Maidanak I-band observations
  40. GRB050820A: RTT150 optical observations
  41. GRB 050822: ROTSE-III Prompt Optical Limits
  42. GRB050820A: Radio Observation
  43. GRB 050820a: NIR Observations by WIRO
  44. GRB 050820B: Swift XRT position
  45. Swift/UVOT photometry of GRB050820
  46. GRB050820: refined XRT analysis
  47. GRB 050820: P60 Temporal Decay Index
  48. GRB 050820: High Resolution Spectroscopy from Keck
  49. GRB050819: refined XRT analysis
  50. GRB050819: RTT150 optical observations
  51. GRB 050820: Swift detection of a GRB
  52. GRB 050817: Optical observations
  53. GRB 050815: Radio Observation
  54. GRB050814: Radio Observation
  55. GRB050817: Negative Optical Observations
  56. GRB050817: Swift-BAT Detection of a burst
  57. GRB050815: Optical afterglow detection by Swift UVOT
  58. GRB 050813: Radio Observations
  59. GRB 050730: Third Epoch WSRT Radio Observations
  60. GRB 050813: Gemini Spectra Revisited
  61. GRB050814: P60 Optical Afterglow Candidate
  62. GRB 050813: Non-fading of afterglow candidate
  63. GRB050813: Gemini Imaging
  64. GRB 050813: Gemini spectroscopy and redshifts of galaxies B and C
  65. GRB 050813: Magellan detection of a high redshift galaxy cluster
  66. GRB050813: RTT150 optical observations
  67. GRB 050813: I-band observations
  68. GRB050813, SDSS pre-burst observations
  69. GRB 050813: Photometry of object in XRT error circle
  70. RBO GRB 050714A and GRB 050716 observations
  71. GRB050813 (Swift 150139): P60 Observations
  72. GRB050803: CrAO optical observations, no OT candidate
  73. GRB 050730: WSRT Radio Observations
  74. GRB 050803: PROMPT BVRcIc Observations
  75. GRB 050807: ROTSE-III Optical Limits
  76. GRB 050730, optical observation
  77. GRB050805a : Null detection report
  78. GRB050730, optical observations
  79. GRB050803, optical observations
  80. Swift-BAT trigger 149118 is very likely not a GRB
  81. GRB050805b: MASTER optical observations
  82. GRB050802: TNG optical observations
  83. GRB050803: Radio Observation
  84. GRB 050803: RTT150 optical observations
  85. GRB050730: Radio Detection
  86. GRB050803: CrAO optical observations, possible OT candidate
  87. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  88. GRB 050803: Keck Observations
  89. GRB 050802.422: Fading of the afterglow and detection of the host
  90. GRB 050803, optical observations
  91. GRB 050803: Magellan Observations
  92. GRB 050803: TAROT optical limits
  93. GRB050803: MASTER optical observations
  94. GRB050802: Tentative absorption redshift
  95. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  96. GRB 050802: Swift/UVOT optical and UV detections
  97. GRB050802: CrAO optical observations
  98. GRB 050730: OHP optical observations
  99. GRB 050802: Swift/UVOT observations
  100. GRB 050802: Swift Gamma-ray Burst

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