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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"

21952 results found.

  1. Swift/UVOT observations of GRB060306
  2. GRB 060306: PROMPT Observations
  3. GRB 060218: RTT150 optical observations
  4. GRB060218/SN 2006aj: optical observation in V
  5. GRB060218/SN 2006aj: optical observation
  6. GRB 060121: HST observations
  7. GRB 060223b: Swift/UVOT Upper Limits
  8. GRB 060218/SN 2006aj: K-380 optical observations
  9. GRB 060218/SN 2006aj, SMARTS optical/IR observations
  10. GRB200618: optical polarimetry and photometry
  11. GRB 060218/SN 2006aj: ABT observations
  12. GRB 060218/SN 2006aj: REM optical and near-infrared observations
  13. GRB 060218/SN 2006aj: WIRO optical observations
  14. GRB 060218/SN 2006aj: RBO optical observations
  15. GRB 060218: Refined analysis of the radio afterglow
  16. GRB 060223A:Xinglong optical limits
  17. Correction to GCN 4816 on GRB060218
  18. GRB 060218/SN 2006aj: optical observations
  19. GRB060218: Optical brightening in V and R
  20. GRB 060223: Keck redshift
  21. GRB 060218: rebrightening
  22. GRB 060218: emergence of the underlying SN spectrum
  23. GRB 060218: Decline in r-band flux
  24. GRB 060218: spectroscopic observations
  25. GRB 060218: Likely an underluminous GRB
  26. GRB060218: Optical Spectroscopy of GRB-SN
  27. GRB 060218: Optical Observations at Xinglong Obs.
  28. GRB 060219: SDSS galaxy inside XRT error circle
  29. GRB060218: UV Detection and Light Curves
  30. GRB060219: SARA Observations
  31. GRB 051221B: Swift-XRT Team Refined Analysis
  32. GRB060218: Radio Afterglow Discovery
  33. GRB 060218: MDM Redshift
  34. GRB 060218: optical/nIR observations at La Palma
  35. GRB060219: SDSS pre-burst observations
  36. Oddball GRB 060218, transient or GRB?
  37. Brightening of the Optical Counterpart of the Possible GRB 060218
  38. GRB 060218: MDM Observations
  39. GRB 060218: Pre-burst detection of a possible host galaxy
  40. Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
  41. GRB060218 : SDSS pre-burst observations
  42. GRB 060213: optical afterglow not confirmed
  43. Swift UVOT observations of GRB060213
  44. GRB 060211B: Skynet Observations
  45. GRB 060213: optical afterglow candidate
  46. GRB060213: Swift XRT observations and possible afterglow candidate
  47. GRB 060211b: WIRO NIR Observations
  48. GRB060206: Swift XRT observations of an unbroken powerlaw decay
  49. GRB 060210: Radio Observations
  50. GRB 060211a: WIRO NIR Observations
  51. GRB060211B: REM optical and NIR observations
  52. GRB060121: optical observations
  53. GRB060110: optical observations
  54. GRB060105: optical observations
  55. GRB 060210: ARC NIR Detection of Afterglow and Possible Host Galaxy
  56. GRB 060211b: P60 Observations
  57. GRB 050826: Optical Afterglow and Host Galaxy
  58. GRB 060210: Optical Observations
  59. GRB060206, optical observations
  60. GRB060210: Optical Observations
  61. GRB060210: Early Optical Observations
  62. GRB 060210: optical evolution
  63. GRB060210:Faulkes Telescope North Afterglow Confirmation
  64. GRB 060210: candidate afterglow
  65. GRB 060206: Swift/UVOT Observations
  66. GRB060209: RTT150 optical observations
  67. GRB 060206: near-infrared observations (JK' imaging)
  68. GRB 060206: WSRT Radio Observations
  69. GRB 060206: TTT Observations
  70. GRB 060206: Tenagra II Observations
  71. GRB060204a: Swift XRT Source is not GRB Afterglow
  72. GRB 060206: optical observations at Asiago
  73. Orphan GRB Afterglow candidate
  74. GRB 060204b: pseudo-z from spectral parameters of the prompt emission
  75. GRB 060206: Lick 3m Spectroscopy
  76. GRB 060206: Super-LOTIS observations
  77. GRB060204A: Swift/UVOT observations
  78. GRB 060206 : Lulin optical observations
  79. GRB060206: SDSS Pre-Burst Observations
  80. GRB060206: Swift XRT Refined Analysis
  81. GRB060206: P60 Optical Observations
  82. GRB 060206: KAIT observations
  83. GRB060206: SARA Detection
  84. GRB 060206: RAPTOR observations of afterglow candidate variability.
  85. GRB060204a: Swift XRT Detection of an Afterglow Candidate
  86. GRB060206: Optical afterglow
  87. GRB060203: WHT Z-band observations
  88. GRB060204C: optical observation
  89. GRB 060204A: FRAM optical observations
  90. GRB 060204C: optical observations
  91. GRB 060204C: OSN limits
  92. GRB 060204b: Keck/LRIS Afterglow Confirmation
  93. GRB 060124: Radio Observations
  94. GRB060204B - SDSS pre-burst observations
  95. GRB 060202: UKIRT/WFCAM K-band and KeckI/LRIS I-band Observation
  96. GRB 060203: RTT150 optical observations
  97. GRB 060203: IR Counterpart
  98. GRB060203: Observations with SARA
  99. GRB 060203: P60 Confirmation of Optical Afterglow
  100. Possible GRB 060203: candidate optical counterpart

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