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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"

17219 results found.

  1. GRB030418: Upper limits from recent and historical observations.
  2. GRB030418: Kiso near infrared observations
  3. GRB030329: Optical Observations
  4. GRB 030329: SARA Optical Observations
  5. OT GRB 030329: early spectrum
  6. IPN triangulation of GRB030414 (small error box)
  7. GRB 030329 and SN 2003dh
  8. GRB030329, optical position
  9. GRB 030329 VLBA Observations
  10. GRB 030329, light curve flattens
  11. Kiso observation of the GRB030329 at April 6
  12. GRB 030329, color evolution
  13. GRB030328, UBVRcIc field photometry
  14. GRB 030329 Optical observations
  15. GRB 030329, color evolution
  16. GRB030329: Kiso B and R band observations
  17. SDSS 0.5m PT observations of GRB030329 (correction)
  18. SDSS 0.5m PT observations of GRB030329
  19. GRB030329: final R-band light curve by MASTER
  20. GRB030329, new UBVRcIc field photometry
  21. GRB 030329 , SPM optical observations
  22. GRB030329: Optical observations at Teramo
  23. GRB 030329: Radio observations at GMRT
  24. GRB 030329: Additional Mt. Laguna Optical Observations
  25. GRB 030329: Observations with ANDICAM
  26. GRB 030329: optical observations
  27. GRB 030324: Optical and NIR Observations
  28. GRB030329: R band light curve by MASTER
  29. GRB030329 - Light curve flattening
  30. GRB 030324, optical search
  31. GRB 030329, optical observations
  32. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  33. GRB030329, BVRcIc field photometry
  34. GRB030329, SPM optical observations
  35. GRB 030329, optical photometry
  36. GRB030329 optical observations
  37. GRB 030329: Optical pre-Imaging
  38. GRB 030329: visual observations
  39. GRB 030329: Upper limit from 5.6 hours before trigger
  40. GRB030328: X-ray Afterglow Observed with Chandra
  41. GRB 030329, R-band observations
  42. GRB030329: Upper limits from recent and historical observations.
  43. GRB 030329: Optical Afterglow Observations
  44. GRB 030329: precise position from Kyoto images
  45. GRB 030328: Optical observations
  46. GRB 030328: optical observations
  47. GRB 030329: Optical afterglow fading
  48. GRB 030328: OT photometry
  49. GRB030328: optical photometry at the TNG
  50. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  51. GRB 030328: Optical observations
  52. GRB030324 optical observation
  53. GRB030131, BVRcIc field photometry
  54. Possible GRB030323 localized by INTEGRAL
  55. GRB030323: Detection on 2003/03/24
  56. GRB030323: V, R, I photometry
  57. VLT/FORS2 spectra of GRB 030323
  58. GRB030323, optical observations
  59. GRB030324, BVRcIc field photometry
  60. GRB030323, BVRcIc field calibration
  61. Possible GRB 030320 localized by INTEGRAL
  62. GRB 030226: Optical observations
  63. GRB030226: Analysis of Chandra data
  64. GRB030226, BVRc observations
  65. Chandra detection of the X-ray afterglow of GRB 030226
  66. GRB030227: Kiso optical upper limit
  67. GRB030227, BVRcIc field photometry
  68. GRB030226, BVRcIc field calibration
  69. GRB 030228, optical observations
  70. GRB 030227: Confirmed Optical Afterglow (S1-A)
  71. GRB 030226: Optical observations
  72. GRB 030227: fading of candidate optical afterglow 'S1-A'
  73. GRB030227:Optical observations
  74. GRB 030227, possible optical counterpart of XMM-Newton source
  75. GRB030227: Kiso optical observations
  76. GRB 030227: Kyoto optical observation
  77. GRB030227: refined INTEGRAL position
  78. GRB030227 localized by INTEGRAL
  79. GRB030226: ESI spectroscopy
  80. GRB 030226 simultaneous optical observations
  81. GRB 030226, optical observations
  82. GRB030226: Optical decay index
  83. GRB 030131: marginal optical detection
  84. GRB 030204: Optical Observations
  85. GRB030204 field photometry
  86. GRB020819: Kiso R and I band observations
  87. GRB030131: Candidate Optical Afterglow
  88. GRB 030131, optical observations
  89. GRB 030131: afterglow candidate
  90. GRB 030115, late-time optical observations
  91. GRB 020819: Host galaxy at Radio Position
  92. GRB 030131 optical observations
  93. GRB 030131 optical observations
  94. A long GRB detected by INTEGRAL
  95. GRB 030115, simultaneous observations by BOOTES-1
  96. GRB 030115: IR observations with IRSF/SIRIUS
  97. GRB030115, afterglow candidate
  98. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  99. GRB 030115 : Possible IR counterpart
  100. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts

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