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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"

45467 results found.

  1. GRB021113 (=H2449): A Long GRB Localized by HETE
  2. GRB 021112: Optical Observations
  3. GRB 021112: R-band search
  4. IPN triangulation of GRB021108 (large error box)
  5. GRB021112 (=H2448): A Long GRB Localized by HETE
  6. GRB 021016: Optical Observations
  7. IPN triangulation of GRB021109 (annulus)
  8. IPN triangulation of GRB021108 (annulus)
  9. GRB021004: Near infrared spectroscopy
  10. GRB021104: Optical Observations
  11. IPN triangulation of GRB021104 (annulus)
  12. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  13. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  14. SGR1900+14 activity, November 2-4, 2002
  15. Spectropolarimetry of GRB021004
  16. GRB021104: Optical observations
  17. GRB021104: optical observations
  18. GRB021104: Candidate present in DSS
  19. GRB021104: possible optical afterglow
  20. IPN triangulation of GRB021102 (annulus)
  21. Detection of activity from SGR 1900+14 with the RXTE/PCA
  22. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  23. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  24. IPN triangulation of GRB021025 (portion of annulus)
  25. IPN triangulation of GRB021027 (single large error box)
  26. GRB021004, late-time optical observations
  27. IPN triangulation of GRB021027 (two large error boxes)
  28. IPN triangulation of GRB021027 (annulus)
  29. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  30. IPN triangulation of GRB021025 (annulus)
  31. IPN triangulation of SGR1900+14, October 22 2002
  32. GRB 021004: optical observations
  33. IPN triangulation of GRB021023 (small error boc)
  34. GRB021004: Optical Observations
  35. GRB 020813; likely host galaxy.
  36. IPN triangulation of GRB021020 (smaller error box)
  37. GRB021021(=XRF 021021): An X-ray Flash Localized by HETE
  38. IPN triangulation of GRB021020
  39. GRB 021008, radio observations
  40. GRB 021016, optical observations
  41. GRB 021004: VRI observations at TNG: possible break
  42. GRB021016, optical observations
  43. SGR1900+14: burst on October 10 2002
  44. GRB 021008, optical observations
  45. GRB021016(=H2397): A Long GRB Localized by HETE
  46. IPN triangulation of GRB021016 (area corrected)
  47. IPN triangulation of GRB021016 (small error box)
  48. GRB021004: Optical Observations
  49. IPN triangulation of GRB021014 (large error box)
  50. IPN triangulation of GRB021013 (single error box)
  51. GRB 021004: optical spectroscopy on Oct 11
  52. IPN triangulation of GRB021013 (two small error boxes)
  53. GRB021004: High-resolution optical spectroscopy
  54. IPN triangulation of GRB021013 (annulus)
  55. XRF 020903: flattening of the optical light curve.
  56. GRB021004, UBVRcIc field photometry update
  57. IPN triangulation of GRB021008 (single error box)
  58. GRB021004: Optical Observations
  59. GRB 021004 submm observations
  60. IPN triangulation of GRB021008B (annulus)
  61. IPN triangulation of GRB021008 (two small error boxes)
  62. GRB021004 Chandra HETG Observations
  63. GRB 021004: Optical/NIR Observations
  64. GRB 021004: Additional V-band Polarimetric Observations
  65. GRB021004: optical observation
  66. GRB 021004: Host Galaxy Star Formation Rate
  67. GRB 021004 submm observations
  68. GRB 021004: WC wind?
  69. IPN triangulation of GRB021008
  70. GRB021004: NIR and Optical observations
  71. GRB 021004: Optical measurement at OHP
  72. GRB 021004: Optical observations, AUDE network
  73. GRB 021004 - VLA Radio Observations
  74. GRB 021004 - Unusual Radio-to-Submm Spectrum
  75. GRB 021004: optical spectroscopy
  76. IPN triangulation of GRB021007 (annulus)
  77. XRF 020903 spectrum
  78. GRB 021004: HST/STIS spectroscopic observations
  79. GRB021004: optical observations and predicted break time
  80. GRB021004: BVRc photometry
  81. GRB 021004 redshift
  82. GRB021004 radio observation
  83. GRB021004: restart of optical decay
  84. GRB 021004: Optical Decay
  85. GRB 021004 continued IR fading
  86. HETE fluences for GRB021004
  87. GRB 021004, spectroscopic observations
  88. GRB021004: not fading anymore?
  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. GRB 021004: Optical Decay
  94. GRB021004, astrometric position
  95. GRB021004, Optical Observations
  96. IRAM Millimeter detection of GRB 021004
  97. GRB 021004: Optical observations at RIKEN
  98. GRB 021004 radio observation
  99. GRB 021004: Optical Observations
  100. GRB021004: continued fading

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