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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"

32793 results found.

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

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