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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').
Advanced Search

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"

42595 results found.

  1. IPN triangulation of GRB021109 (annulus)
  2. IPN triangulation of GRB021108 (annulus)
  3. GRB021004: Near infrared spectroscopy
  4. GRB021104: Optical Observations
  5. IPN triangulation of GRB021104 (annulus)
  6. GRB021104(=H2434): A Long, X-Ray-Rich GRB Localized by HETE
  7. IPN triangulation of bursts from SGR1900+14, November 1-2, 2002
  8. SGR1900+14 activity, November 2-4, 2002
  9. Spectropolarimetry of GRB021004
  10. GRB021104: Optical observations
  11. GRB021104: optical observations
  12. GRB021104: Candidate present in DSS
  13. GRB021104: possible optical afterglow
  14. IPN triangulation of GRB021102 (annulus)
  15. Detection of activity from SGR 1900+14 with the RXTE/PCA
  16. IPN triangulation of a burst from SGR1900+14 on November 01, 2002
  17. IPN triangulation of a burst from SGR1900+14 on October 29 2002
  18. IPN triangulation of GRB021025 (portion of annulus)
  19. IPN triangulation of GRB021027 (single large error box)
  20. GRB021004, late-time optical observations
  21. IPN triangulation of GRB021027 (two large error boxes)
  22. GRB 021023: Infrared Imaging
  23. IPN triangulation of GRB021027 (annulus)
  24. GRB 021023: Curious K-band Source(s) Just Outside of IPN Localization
  25. IPN triangulation of GRB021025 (annulus)
  26. IPN triangulation of SGR1900+14, October 22 2002
  27. GRB 021004: optical observations
  28. IPN triangulation of GRB021023 (small error boc)
  29. GRB 020813; likely host galaxy.
  30. IPN triangulation of GRB021020 (smaller error box)
  31. GRB021021(=XRF 021021): An X-ray Flash Localized by HETE
  32. IPN triangulation of GRB021020
  33. GRB 021008, radio observations
  34. GRB 021004: VRI observations at TNG: possible break
  35. GRB021016, optical observations
  36. SGR1900+14: burst on October 10 2002
  37. GRB 021008, optical observations
  38. GRB021016(=H2397): A Long GRB Localized by HETE
  39. IPN triangulation of GRB021016 (small error box)
  40. GRB021004: Optical Observations
  41. IPN triangulation of GRB021014 (large error box)
  42. IPN triangulation of GRB021013 (single error box)
  43. GRB 021004: optical spectroscopy on Oct 11
  44. IPN triangulation of GRB021013 (two small error boxes)
  45. GRB021004: High-resolution optical spectroscopy
  46. IPN triangulation of GRB021013 (annulus)
  47. XRF 020903: flattening of the optical light curve.
  48. GRB021004, UBVRcIc field photometry update
  49. IPN triangulation of GRB021008 (single error box)
  50. GRB021004: Optical Observations
  51. GRB 021004 submm observations
  52. IPN triangulation of GRB021008B (annulus)
  53. IPN triangulation of GRB021008 (two small error boxes)
  54. GRB021004 Chandra HETG Observations
  55. GRB 021004: Optical/NIR Observations
  56. GRB 021004: Additional V-band Polarimetric Observations
  57. GRB021004: optical observation
  58. GRB 021004: Host Galaxy Star Formation Rate
  59. GRB 021004 submm observations
  60. GRB 021004: WC wind?
  61. IPN triangulation of GRB021008
  62. GRB021004: NIR and Optical observations
  63. GRB 021004: Optical measurement at OHP
  64. GRB 021004: Optical observations, AUDE network
  65. GRB 021004 - VLA Radio Observations
  66. GRB 021004 - Unusual Radio-to-Submm Spectrum
  67. GRB 021004: optical spectroscopy
  68. IPN triangulation of GRB021007 (annulus)
  69. XRF 020903 spectrum
  70. GRB 021004: HST/STIS spectroscopic observations
  71. GRB021004: optical observations and predicted break time
  72. GRB021004: BVRc photometry
  73. GRB 021004 redshift
  74. GRB021004 radio observation
  75. GRB021004: restart of optical decay
  76. GRB 021004 continued IR fading
  77. HETE fluences for GRB021004
  78. GRB 021004, spectroscopic observations
  79. GRB021004: not fading anymore?
  80. GRB 021004: Optical Photometry at 2.5 Days
  81. GRB 021004: polarimetric observations
  82. GRB 021004: V-band Polarimetric Observations
  83. GRB021004: Update Bisei photometric data
  84. GRB 021004: Optical Decay
  85. GRB021004, astrometric position
  86. GRB021004, Optical Observations
  87. IRAM Millimeter detection of GRB 021004
  88. GRB 021004: Optical observations at RIKEN
  89. GRB 021004 radio observation
  90. GRB 021004: Optical Observations
  91. GRB021004: continued fading
  92. GRB 021004: Optical Photometry at 1.5 Days
  93. GRB021004, Optical Observations
  94. GRB021004, BVRcIc field photometry
  95. GRB 021004: Optical observations
  96. GRB 021004: optical counterpart
  97. GRB 021004, optical observations
  98. GRB021004: Optical Spectroscopy
  99. GRB 021004: Optical Observations
  100. GRB 021004, SPM optical observations

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