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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"

24619 results found.

  1. GRB 021112: Evidence for Another Dark Optical Afterglow
  2. GRB 021219: OSN optical observations
  3. GRB021219, optical observations
  4. GRB021219, optical observation by MASTER
  5. VLT spectra of GRB 021211 revisited
  6. GRB021219: a long GRB localized by INTEGRAL
  7. GRB021211: APO optical observations
  8. XRF 020903 : HST observations
  9. GRB 021201: Optical Observations
  10. GRB 021211: CTIO observations
  11. GRB021211, BVRI field photometry
  12. GRB021211: Optical observations in CrAO
  13. GRB 021211, optical observations
  14. GRB021211: Kiso Observations
  15. GRB 021201, optical observations
  16. GRB021211: Optical observations
  17. GRB 021201 (short/hard), NOT observations
  18. SUB-MM SEARCH FOR GRB 021211
  19. Chandra observation of the IPN error box of GRB021201 (short/hard)
  20. GRB 021211, R- and I-band observations
  21. GRB021211 - Upper limits from recent and historical observations
  22. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  23. IPN triangulation of GRB021206 (small error box)
  24. IPN triangulation of GRB021205 (large error box)
  25. GRB021201, BVRcIc field photometry
  26. GRB 021201: BOOTES simultaneous optical observations
  27. IPN triangulation of GRB021201 (short/hard burst, small error box)
  28. GRB021004, late time optical observations
  29. GRB021004 Chandra Observation
  30. IPN detection of continued SGR1900+14 activity
  31. Improved IPN error box for GRB021125
  32. IPN BURST POSITION
  33. IPN triangulation of GRB021125 (INTEGRAL BURST)
  34. GRB021125 : A long GRB localized by INTEGRAL
  35. IPN confirmation of the reactivation of SGR1900+14
  36. GRB021113, SPI ACS observation
  37. GRB 021112: Afterglow or Variable Star?
  38. GRB021113: optical observations at Bisei
  39. GRB 021113: Evidence for a Dark Optical Afterglow
  40. GRB021112, BVRI field photometry
  41. GRB 021112: Variable Source in R-band search
  42. GRB021112: Optical Observations
  43. IPN triangulation of GRB021113 (=H2449; annulus)
  44. GRB 021113: Optical observations
  45. GRB 021112: RAPTOR Observations
  46. GRB021113 (=H2449): A Long GRB Localized by HETE
  47. GRB021112 (=H2448): A Long GRB Localized by HETE
  48. GRB 021016: Optical Observations
  49. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  50. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  51. SGR1900+14 activity, November 2-4, 2002
  52. GRB021104: optical observations
  53. Detection of activity from SGR 1900+14 with the RXTE/PCA
  54. IPN triangulation of GRB021027 (single large error box)
  55. IPN triangulation of GRB021027 (two large error boxes)
  56. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  57. GRB 021004: optical observations
  58. IPN triangulation of GRB021023 (small error boc)
  59. GRB 020813; likely host galaxy.
  60. IPN triangulation of GRB021020 (smaller error box)
  61. IPN triangulation of GRB021020
  62. GRB 021008, optical observations
  63. IPN triangulation of GRB021016 (small error box)
  64. IPN triangulation of GRB021014 (large error box)
  65. IPN triangulation of GRB021013 (single error box)
  66. GRB 021004: optical spectroscopy on Oct 11
  67. IPN triangulation of GRB021013 (two small error boxes)
  68. GRB021004: High-resolution optical spectroscopy
  69. XRF 020903: flattening of the optical light curve.
  70. GRB021004, UBVRcIc field photometry update
  71. IPN triangulation of GRB021008 (single error box)
  72. GRB 021004 submm observations
  73. IPN triangulation of GRB021008 (two small error boxes)
  74. GRB021004 Chandra HETG Observations
  75. GRB 021004: Optical/NIR Observations
  76. GRB 021004: Additional V-band Polarimetric Observations
  77. GRB021004: optical observation
  78. GRB 021004: Host Galaxy Star Formation Rate
  79. GRB 021004 submm observations
  80. GRB 021004: WC wind?
  81. GRB021004: NIR and Optical observations
  82. GRB 021004: Optical observations, AUDE network
  83. GRB 021004 - VLA Radio Observations
  84. GRB 021004 - Unusual Radio-to-Submm Spectrum
  85. GRB 021004: optical spectroscopy
  86. IPN triangulation of GRB021007 (annulus)
  87. GRB021004: optical observations and predicted break time
  88. GRB021004: BVRc photometry
  89. GRB021004 radio observation
  90. HETE fluences for GRB021004
  91. GRB 021004: Optical Photometry at 2.5 Days
  92. GRB 021004: polarimetric observations
  93. GRB 021004: V-band Polarimetric Observations
  94. GRB021004: Update Bisei photometric data
  95. IRAM Millimeter detection of GRB 021004
  96. GRB 021004 radio observation
  97. GRB 021004: Optical Photometry at 1.5 Days
  98. GRB021004, BVRcIc field photometry
  99. GRB021004: Optical Spectroscopy
  100. GRB 021004 radio search

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