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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"

24617 results found.

  1. GRB021219, optical observations
  2. GRB021219, optical observation by MASTER
  3. VLT spectra of GRB 021211 revisited
  4. GRB021219: a long GRB localized by INTEGRAL
  5. GRB021211: APO optical observations
  6. XRF 020903 : HST observations
  7. GRB 021201: Optical Observations
  8. GRB 021211: CTIO observations
  9. GRB021211, BVRI field photometry
  10. GRB021211: Optical observations in CrAO
  11. GRB 021211, optical observations
  12. GRB021211: Kiso Observations
  13. GRB 021201, optical observations
  14. GRB021211: Optical observations
  15. GRB 021201 (short/hard), NOT observations
  16. SUB-MM SEARCH FOR GRB 021211
  17. Chandra observation of the IPN error box of GRB021201 (short/hard)
  18. GRB 021211, R- and I-band observations
  19. GRB021211 - Upper limits from recent and historical observations
  20. GRB021211 (=H2493): A Bright, Long GRB Localized by HETE-2 in Near-Real Time
  21. IPN triangulation of GRB021206 (small error box)
  22. IPN triangulation of GRB021205 (large error box)
  23. GRB021201, BVRcIc field photometry
  24. GRB 021201: BOOTES simultaneous optical observations
  25. IPN triangulation of GRB021201 (short/hard burst, small error box)
  26. GRB021004, late time optical observations
  27. GRB021004 Chandra Observation
  28. IPN detection of continued SGR1900+14 activity
  29. Improved IPN error box for GRB021125
  30. IPN BURST POSITION
  31. IPN triangulation of GRB021125 (INTEGRAL BURST)
  32. GRB021125 : A long GRB localized by INTEGRAL
  33. IPN confirmation of the reactivation of SGR1900+14
  34. GRB021113, SPI ACS observation
  35. GRB 021112: Afterglow or Variable Star?
  36. GRB021113: optical observations at Bisei
  37. GRB 021113: Evidence for a Dark Optical Afterglow
  38. GRB021112, BVRI field photometry
  39. GRB 021112: Variable Source in R-band search
  40. GRB021112: Optical Observations
  41. IPN triangulation of GRB021113 (=H2449; annulus)
  42. GRB 021113: Optical observations
  43. GRB 021112: RAPTOR Observations
  44. GRB021113 (=H2449): A Long GRB Localized by HETE
  45. GRB021112 (=H2448): A Long GRB Localized by HETE
  46. GRB 021016: Optical Observations
  47. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  48. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  49. SGR1900+14 activity, November 2-4, 2002
  50. GRB021104: optical observations
  51. Detection of activity from SGR 1900+14 with the RXTE/PCA
  52. IPN triangulation of GRB021027 (single large error box)
  53. IPN triangulation of GRB021027 (two large error boxes)
  54. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  55. GRB 021004: optical observations
  56. IPN triangulation of GRB021023 (small error boc)
  57. GRB 020813; likely host galaxy.
  58. IPN triangulation of GRB021020 (smaller error box)
  59. IPN triangulation of GRB021020
  60. GRB 021008, optical observations
  61. IPN triangulation of GRB021016 (small error box)
  62. IPN triangulation of GRB021014 (large error box)
  63. IPN triangulation of GRB021013 (single error box)
  64. GRB 021004: optical spectroscopy on Oct 11
  65. IPN triangulation of GRB021013 (two small error boxes)
  66. GRB021004: High-resolution optical spectroscopy
  67. XRF 020903: flattening of the optical light curve.
  68. GRB021004, UBVRcIc field photometry update
  69. IPN triangulation of GRB021008 (single error box)
  70. GRB 021004 submm observations
  71. IPN triangulation of GRB021008 (two small error boxes)
  72. GRB021004 Chandra HETG Observations
  73. GRB 021004: Optical/NIR Observations
  74. GRB 021004: Additional V-band Polarimetric Observations
  75. GRB021004: optical observation
  76. GRB 021004: Host Galaxy Star Formation Rate
  77. GRB 021004 submm observations
  78. GRB 021004: WC wind?
  79. GRB021004: NIR and Optical observations
  80. GRB 021004: Optical observations, AUDE network
  81. GRB 021004 - VLA Radio Observations
  82. GRB 021004 - Unusual Radio-to-Submm Spectrum
  83. GRB 021004: optical spectroscopy
  84. IPN triangulation of GRB021007 (annulus)
  85. GRB021004: optical observations and predicted break time
  86. GRB021004: BVRc photometry
  87. GRB021004 radio observation
  88. HETE fluences for GRB021004
  89. GRB 021004: Optical Photometry at 2.5 Days
  90. GRB 021004: polarimetric observations
  91. GRB 021004: V-band Polarimetric Observations
  92. GRB021004: Update Bisei photometric data
  93. IRAM Millimeter detection of GRB 021004
  94. GRB 021004 radio observation
  95. GRB 021004: Optical Photometry at 1.5 Days
  96. GRB021004, BVRcIc field photometry
  97. GRB021004: Optical Spectroscopy
  98. GRB 021004 radio search
  99. XRF020903, BVRI field photometry
  100. XRF020903: TNG and Asiago photometry

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