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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"

32507 results found.

  1. GRB 021219: OSN optical observations
  2. GRB021219: Radio Observations
  3. GRB021219, optical observations
  4. IPN triangulation of GRB021219 - CORRECTION
  5. IPN triangulation of GRB021219
  6. GRB021219, optical observation by MASTER
  7. GRB021219: Correction to GCN 1766
  8. VLT spectra of GRB 021211 revisited
  9. GRB021219: a long GRB localized by INTEGRAL
  10. GRB021211: APO optical observations
  11. IPN detection of continued activity from SGR1806-20
  12. XRF 020903 : HST observations
  13. GRB 021201: Optical Observations
  14. GRB 021211, optical observations
  15. GRB 021211: CTIO observations
  16. GRB021211: Measurement of Early Time Afterglow
  17. VLT spectrum of GRB 021211
  18. GRB 021211: early break in light curve
  19. GRB021211, BVRI field photometry
  20. GRB021211: Optical observations in CrAO
  21. GRB 021211, IR observations
  22. GRB 021211, optical observations
  23. GRB 021211: Optical Observations
  24. GRB021211: Kiso Observations
  25. GRB 021201, optical observations
  26. GRB 021211: Radio Observations
  27. GRB021211: Optical observations
  28. GRB 021201 (short/hard), NOT observations
  29. SUB-MM SEARCH FOR GRB 021211
  30. Chandra observation of the IPN error box of GRB021201 (short/hard)
  31. GRB 021211, R- and I-band observations
  32. GRB021211 - Upper limits from recent and historical observations
  33. GRB021211, OT at 108 s
  34. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  35. HETE 2493: Optical observations
  36. GRB 021125: Radio Observations
  37. IPN triangulation of GRB021206 (small error box)
  38. GRB 021104, GRB 021112 and GRB 021113 - Milagro GeV/TeV Observations
  39. GRB021201, BVRcIc field photometry
  40. GRB 021201, Radio Observations
  41. GRB 021201: Optical Observations
  42. GRB 021201: BOOTES simultaneous optical observations
  43. GRB021004, late time optical observations
  44. GRB021004 Chandra Observation
  45. GRB021125 refined position
  46. IPN triangulation of GRB021125B (two large error boxes)
  47. IPN triangulation of GRB021119 (large error box)
  48. Improved IPN error box for GRB021125
  49. IPN BURST POSITION
  50. IPN confirmation of the reactivation of SGR1900+14
  51. GRB021113, SPI ACS observation
  52. GRB 021112: Afterglow or Variable Star?
  53. GRB021113: optical observations at Bisei
  54. GRB 021113: Evidence for a Dark Optical Afterglow
  55. GRB 021112: Variable Source in R-band search
  56. GRB021112: Optical Observations
  57. IPN triangulation of GRB021109 (portion of annulus)
  58. IPN triangulation of GRB021113 (=H2449; annulus)
  59. IPN triangulation of GRB021108 (CORRECTION; TWO LARGE ERROR BOXES)
  60. GRB 021113: Optical Observations
  61. GRB 021113: Optical Observations
  62. GRB021113 (=H2449): A Long GRB Localized by HETE
  63. GRB 021112: Optical Observations
  64. GRB 021112: R-band search
  65. IPN triangulation of GRB021108 (large error box)
  66. GRB021112 (=H2448): A Long GRB Localized by HETE
  67. GRB 021016: Optical Observations
  68. GRB021004: Near infrared spectroscopy
  69. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  70. Spectropolarimetry of GRB021004
  71. GRB021104: optical observations
  72. GRB021104: Candidate present in DSS
  73. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  74. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  75. IPN triangulation of GRB021025 (portion of annulus)
  76. IPN triangulation of GRB021027 (single large error box)
  77. GRB021004, late-time optical observations
  78. IPN triangulation of GRB021027 (two large error boxes)
  79. GRB 021023: Infrared Imaging
  80. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  81. IPN triangulation of SGR1900+14, October 22 2002
  82. GRB 021004: optical observations
  83. GRB021004: Optical Observations
  84. GRB 020813; likely host galaxy.
  85. IPN triangulation of GRB021020 (smaller error box)
  86. GRB021021(=XRF 021021): An X-ray Flash Localized by HETE
  87. GRB 021008, radio observations
  88. GRB 021016, optical observations
  89. GRB 021004: VRI observations at TNG: possible break
  90. GRB021016, optical observations
  91. GRB 021008, optical observations
  92. GRB021016(=H2397): A Long GRB Localized by HETE
  93. IPN triangulation of GRB021016 (area corrected)
  94. IPN triangulation of GRB021016 (small error box)
  95. GRB021004: Optical Observations
  96. IPN triangulation of GRB021013 (single error box)
  97. GRB 021004: optical spectroscopy on Oct 11
  98. IPN triangulation of GRB021013 (two small error boxes)
  99. GRB021004: High-resolution optical spectroscopy
  100. XRF 020903: flattening of the optical light curve.

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