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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"

43604 results found.

  1. IPN triangulation of GRB030519B=H2716 (small error box)
  2. GRB 030418: Second Epoch Optical Observations with Magellan
  3. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  4. IPN triangulation of GRB030519 (annulus)
  5. IPN triangulation of GRB030518C (annulus)
  6. IPN triangulation of GRB030518B (annulus)
  7. IPN triangulation of GRB030518A (annulus)
  8. IPN triangulation of GRB030514 (annulus)
  9. HETE GRB030329, correction to Rc Observations in Loiano
  10. IPN triangulation of GRB030513 (annulus)
  11. IPN triangulation of GRB030509B (annulus)
  12. GRB 030329: Optical limit (contemporaneous imaging)
  13. GRB 030501: final TAROT limits
  14. IPN triangulation of GRB030509 (small errror box)
  15. IPN triangulation of GRB030509 (single error box)
  16. GRB030329: RTT150 optical observations
  17. GRB030329, BVRI photometry
  18. GRB030429, refiend optical brightness
  19. GRB 030329: Optical limit (contemporaneous photography)
  20. GRB030418, BVRcIc field photometry
  21. GRB 030429: Redshift of neighbor galaxy
  22. GRB030429, BVRcIc field photometry
  23. GRB030429: RTT150 optical obs., correction to GCN 2208
  24. GRB 030329: High-Resolution Spectroscopy of the Host
  25. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  26. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  27. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  28. GRB030429: RTT150 optical observations, a possible host galaxy
  29. IPN triangulation of GRB030506 (annulus)
  30. IPN triangulation of GRB030505B (large error box)
  31. IPN triangulation of GRB030505A (annulus)
  32. GRB030329: RTT150 optical observations and upper limit for a host
  33. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  34. GRB030501 observation report
  35. GRB030501C triangulation (annulus)
  36. GRB030329: RTT150 optical observations and upper limit for a host
  37. GRB 030429: Radio Observations
  38. GRB 030429: redshift from VLT spectroscopy
  39. GRB030501B triangulation (single error box)
  40. GRB 030329 Optical Observations
  41. GRB030328, optical observation
  42. GRB 030329, BVRI photometry
  43. GRB030429: Optical Observations
  44. GRB030501: TAROT candidate afterglow present in archival images
  45. GRB 030501: TAROT possible candidate counterpart
  46. IPN triangulation of GRB030501 (IBIS event; annulus)
  47. IPN triangulation of GRB030501B (annulus)
  48. GRB 030429: confirmation of afterglow candidate
  49. GRB030429, possible optical counterpart
  50. GRB030501 localized by INTEGRAL
  51. GRB030425: CrAO optical observation
  52. IPN triangulation of GRB030429 (annulus)
  53. IPN triangulation of GRB030428 (two large error boxes)
  54. GRB 030429: ROTSE-III observations
  55. GRB 030324: Radio Observations
  56. GRB030329 observed as a sudden ionospheric disturbance (SID)
  57. IPN triangulation of GRB030426 (annulus)
  58. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  59. IPN triangulation of GRB030425 (single error box)
  60. GRB030329, SPM optical observations (Correction)
  61. GRB030329, SPM optical observations
  62. GRB 030329: Spectral Evolution of SN 2003dh
  63. Optical Observations of GRB 030418 with Magellan
  64. GRB 030329: optical spectropolarimetry at VLT
  65. IPN triangulation of GRB030422C (annulus)
  66. IPN triangulation of GRB030422B (annulus)
  67. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  68. GRB030329: optical polarization
  69. IPN triangulation of GRB030422 (two large error boxes)
  70. GRB 030329 3.5 and 6 cm radio observations at RTF-32 telescope
  71. GRB030329, optical observation
  72. IPN triangulation of GRB030421 (annulus)
  73. MASTER:optical observations GRB030418
  74. MASTER:optical observations probable GRB030414
  75. GRB030329: 444 AAVSO Measurements
  76. IPN triangulation of GRB030419 (annulus)
  77. MASTER:optical observations GRB030416
  78. ROTSE-III prompt optical detections of GRB 030418
  79. GRB030418: Upper limits from recent and historical observations.
  80. GRB 030418: Finder for afterglow candidate
  81. GRB 030418: Optical afterglow candidate
  82. GRB 030329 OT position
  83. GRB030329: Optical Observations
  84. OT GRB 030329: early UBVRcIc spectral evolution
  85. GRB030329, UBVRI polarimetry, R-polarization
  86. GRB 030329: SARA Optical Observations
  87. OT GRB 030329: early spectrum
  88. GRB030329: VR Photometry at TNG
  89. GRB030324: Candidate Optical Afterglow
  90. IPN triangulation of GRB030414 (small error box)
  91. GRB 030413: Optical Observations
  92. GRB 030329 Rc observations
  93. IPN triangulation of GRB030413 (small error box)
  94. IPN triangulation of GRB030410 (annulus)
  95. Superluminal motion in GRB 030329 (Correction)
  96. Superluminal motion in GRB 030329
  97. GRB 030329 and SN 2003dh
  98. GRB030329, optical position
  99. GRB 030329 VLBA Observations
  100. IPN triangulation of GRB030406 (small error box)

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