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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"

32595 results found.

  1. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  2. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  3. GRB030429: RTT150 optical observations, a possible host galaxy
  4. IPN triangulation of GRB030506 (annulus)
  5. IPN triangulation of GRB030505B (large error box)
  6. IPN triangulation of GRB030505A (annulus)
  7. GRB030329: RTT150 optical observations and upper limit for a host
  8. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  9. GRB030501, optical observation
  10. GRB030501C triangulation (annulus)
  11. GRB030329: RTT150 optical observations and upper limit for a host
  12. GRB 030429: Radio Observations
  13. GRB 030429: redshift from VLT spectroscopy
  14. GRB 030429: IR photometry with IRSF/SIRIUS
  15. GRB030501B triangulation (single error box)
  16. GRB 030329 Optical Observations
  17. GRB 030329, BVRI photometry
  18. GRB 030501: TAROT possible candidate counterpart
  19. IPN triangulation of GRB030501 (IBIS event; annulus)
  20. IPN triangulation of GRB030501B (annulus)
  21. GRB 030429: confirmation of afterglow candidate
  22. GRB030429, possible optical counterpart
  23. GRB030501 localized by INTEGRAL
  24. GRB030425: CrAO optical observation
  25. IPN triangulation of GRB030429 (annulus)
  26. IPN triangulation of GRB030428 (two large error boxes)
  27. GRB 030329 Oprical observations in Rozhen observatory
  28. GRB 030429: ROTSE-III observations
  29. GRB 030324: Radio Observations
  30. GRB030329 observed as a sudden ionospheric disturbance (SID)
  31. IPN triangulation of GRB030426 (annulus)
  32. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  33. IPN triangulation of GRB030425 (single error box)
  34. GRB 030329, the review of the sky area in plate archive (1950-1998)
  35. GRB 030329: Spectral Evolution of SN 2003dh
  36. Optical Observations of GRB 030418 with Magellan
  37. GRB 030329: optical spectropolarimetry at VLT
  38. IPN triangulation of GRB030422C (annulus)
  39. IPN triangulation of GRB030422B (annulus)
  40. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  41. GRB030329: optical polarization
  42. IPN triangulation of GRB030422 (two large error boxes)
  43. GRB 030329 3.5 and 6 cm radio observations at RTF-32 telescope
  44. IPN triangulation of GRB030421 (annulus)
  45. MASTER:optical observations GRB030418
  46. MASTER:optical observations probable GRB030414
  47. GRB030329: 444 AAVSO Measurements
  48. IPN triangulation of GRB030419 (annulus)
  49. MASTER:optical observations GRB030416
  50. ROTSE-III prompt optical detections of GRB 030418
  51. GRB030418: Upper limits from recent and historical observations.
  52. GRB030418: Kiso near infrared observations
  53. GRB 030418: Optical afterglow
  54. GRB 030418: Finder for afterglow candidate
  55. GRB 030418: Optical afterglow candidate
  56. GRB 030329 OT position
  57. OT GRB 030329: early UBVRcIc spectral evolution
  58. GRB030329, UBVRI polarimetry, R-polarization
  59. GRB 030329: SARA Optical Observations
  60. OT GRB 030329: early spectrum
  61. GRB030329: VR Photometry at TNG
  62. GRB030324: Candidate Optical Afterglow (Erratum)
  63. GRB030324: Candidate Optical Afterglow
  64. IPN triangulation of GRB030414 (small error box)
  65. GRB 030413: Optical Observations
  66. GRB 030329 Rc observations
  67. IPN triangulation of GRB030413 (small error box)
  68. IPN triangulation of GRB030410 (annulus)
  69. Superluminal motion in GRB 030329 (Correction)
  70. Superluminal motion in GRB 030329
  71. GRB 030329 and SN 2003dh
  72. GRB030329, optical position
  73. GRB 030329 VLBA Observations
  74. IPN triangulation of GRB030406 (small error box)
  75. IPN triangulation of GRB050403 (small error box)
  76. IPN triangulation of GRB030403 (annulus)
  77. GRB 030329: BVRI photometry at Asiago
  78. GRB 030329, light curve flattens
  79. GRB 030329: VLT V-band photometry
  80. If the SN/GRB connection confirmed
  81. GRB 030329: Supernova Confirmed
  82. GRB030329: RTT150 optical observations
  83. GRB030329: Near Infrared Observations at Gunma
  84. GRB030329: HET spectroscopic monitoring
  85. Kiso observation of the GRB030329 at April 6
  86. GRB 030329, color evolution
  87. GRB030328, UBVRcIc field photometry
  88. GRB 030329 Optical observations
  89. GRB 030329, color evolution
  90. GRB 030329: possible color change
  91. GRB030329: RTT150 optical observations
  92. GRB 030329: Supernova Spectrum Emerging
  93. GRB030329: Kiso B and R band observations
  94. GRB030329: RTT150 optical observation
  95. GRB030329: More AAVSO VR obs
  96. GRB030328: R upper limit after 6 hours by MASTER
  97. GRB 030329: BV photographic observations
  98. GRB 030329: SARA Optical Observations
  99. GRB 030329: SARA Optical Observations
  100. GRB030329, fading resumes

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