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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').
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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.

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

24680 results found.

  1. IPN triangulation of GRB030320 (small error box)
  2. Possible GRB 030320 localized by INTEGRAL
  3. IPN triangulation of GRB030306 (single small error box - REVISED)
  4. IPN triangulation of GRB030306 (single small error box)
  5. IPN triangulation of GRB030306 (two small error boxes)
  6. GRB030226, BVRc observations
  7. Chandra detection of the X-ray afterglow of GRB 030226
  8. GRB030227: Kiso optical upper limit
  9. GRB030227, BVRcIc field photometry
  10. GRB030226, BVRcIc field calibration
  11. GRB 030228, optical observations
  12. GRB 030227: Confirmed Optical Afterglow (S1-A)
  13. GRB 030227: fading of candidate optical afterglow 'S1-A'
  14. GRB030227:Optical observations
  15. GRB 030227, possible optical counterpart of XMM-Newton source
  16. GRB030227 - faint tentative OT candidate
  17. GRB 030226, optical observations
  18. XMM-Newton observation of GRB030227
  19. GRB030227: Kiso optical observations
  20. GRB 030227: Kyoto optical observation
  21. GRB 030226, optical light curve
  22. GRB030227 localized by INTEGRAL
  23. GRB 030226 : Predicted light curve
  24. GRB030226: ESI spectroscopy
  25. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  26. GRB 030226 simultaneous optical observations
  27. GRB 030226, optical observations
  28. GRB030226: Optical decay index
  29. GRB 030226 Optical Spectra and R,I,z' Imaging
  30. GRB: Non-Referencing of GCN Circulars.
  31. IPN triangulation of GRB030217 (small error box)
  32. GRB 030131: marginal optical detection
  33. GRB 030204: Optical Observations
  34. GRB030204 field photometry
  35. GRB020819: Kiso R and I band observations
  36. GRB030131: Candidate Optical Afterglow
  37. IPN triangulation of GRB030204 (small error box)
  38. GRB 030131, optical observations
  39. GRB 030131: afterglow candidate
  40. GRB 030115, late-time optical observations
  41. GRB030131: corrected INTEGRAL position
  42. GRB 020819: Host galaxy at Radio Position
  43. IPN triangulation of GRB030131
  44. GRB 030131 optical observations
  45. GRB 030131 optical observations
  46. A long GRB detected by INTEGRAL
  47. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  48. GRB 030115, simultaneous observations by BOOTES-1
  49. GRB 030115: IR observations with IRSF/SIRIUS
  50. IPN triangulation of GRB030115C (large error box)
  51. GRB030115, afterglow candidate
  52. GRB 021211: R-band observations at late-time
  53. GRB030115: Optical Observations, Swiss Telescope at La Silla (ESO, Chile)
  54. GRB 030115 : Possible IR counterpart
  55. GRB030115 (=H2533): A Long GRB Localized by the HETE WXM and SXC
  56. Distribution of INTEGRAL SPI-ACS triggers for GRB bursts
  57. GRB 030115: APO Optical Observations
  58. Information about where HETE will be pointing
  59. VLT spectroscopy of the probable host of GRB 021211
  60. IPN triangulation of GRB030101 (two large error boxes)
  61. GRB 021211: Probable Host and Underlying Supernova
  62. GRB 021112: Evidence for Another Dark Optical Afterglow
  63. GRB 021219: OSN optical observations
  64. GRB021219, optical observations
  65. GRB021219, optical observation by MASTER
  66. VLT spectra of GRB 021211 revisited
  67. GRB021219: a long GRB localized by INTEGRAL
  68. GRB021211: APO optical observations
  69. XRF 020903 : HST observations
  70. GRB 021201: Optical Observations
  71. GRB 021211: CTIO observations
  72. GRB021211, BVRI field photometry
  73. GRB021211: Optical observations in CrAO
  74. GRB 021211, optical observations
  75. GRB021211: Kiso Observations
  76. GRB 021201, optical observations
  77. GRB021211: Optical observations
  78. GRB 021201 (short/hard), NOT observations
  79. SUB-MM SEARCH FOR GRB 021211
  80. Chandra observation of the IPN error box of GRB021201 (short/hard)
  81. GRB 021211, R- and I-band observations
  82. GRB021211 - Upper limits from recent and historical observations
  83. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  84. IPN triangulation of GRB021206 (small error box)
  85. IPN triangulation of GRB021205 (large error box)
  86. GRB021201, BVRcIc field photometry
  87. GRB 021201: BOOTES simultaneous optical observations
  88. IPN triangulation of GRB021201 (short/hard burst, small error box)
  89. GRB021004, late time optical observations
  90. GRB021004 Chandra Observation
  91. IPN detection of continued SGR1900+14 activity
  92. Improved IPN error box for GRB021125
  93. IPN BURST POSITION
  94. IPN triangulation of GRB021125 (INTEGRAL BURST)
  95. GRB021125 : A long GRB localized by INTEGRAL
  96. IPN confirmation of the reactivation of SGR1900+14
  97. GRB021113, SPI ACS observation
  98. GRB 021112: Afterglow or Variable Star?
  99. GRB021113: optical observations at Bisei
  100. GRB 021113: Evidence for a Dark Optical Afterglow

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