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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"

24636 results found.

  1. IPN triangulation of GRB030726 (large error box)
  2. IPN triangulation of GRB030721 (large error box)
  3. XRF030723 Radio Observations
  4. XRF 030723: confirmation of fading optical counterpart
  5. XRF030723(=H2777): Chandra Observations
  6. GRB030723: Upper limits from historical observations
  7. XRF030723: Palomar observations and proposed counterpart
  8. GRB030725 (=H2779): A Bright GRB Localized by HETE
  9. XRF030723 (= H2777): Chandra Observations Scheduled
  10. XRF030723, BVRcIc field photometry correction
  11. XRF030723, ROTSE-III Early Observations
  12. XRF030723, BVRcIc field photometry
  13. XRF 030723, optical observations
  14. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  15. Konus-Wind detection of the bursts from SGR1806-20 region
  16. SGR 1806-20, submm observations
  17. RXTE PCA Observations of SGR1806-20 Region
  18. IPN triangulation of GRB030714 (two large error boxes)
  19. IPN triangulation of GRB030715 (two large error boxes)
  20. GRB030706 triangulation (single large error box)
  21. GRB030329, optical observation in May
  22. IPN triangulation of GRB030626 (single large error box)
  23. IPN triangulation of GRB030626 (two large error boxes)
  24. GRB030329: second XMM-Newton observation
  25. GRB030329 -- RATAN-600 data in April-May
  26. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  27. IPN triangulation of GRB030606 (two alternate error boxes)
  28. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  29. GRB 030528: tentative NIR counterpart
  30. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  31. GRB030528, BVRI field photometry
  32. GRB030329, SPM optical observations
  33. GRB030528: Chandra TOO Planned
  34. GRB030528(=H2724): Revised SXC Localization
  35. GRB 030528 Bisei optical observation
  36. GRB030528 (H2724): A long GRB localized by HETE
  37. GRB 030329: Correction to GCN 2254
  38. GRB 030329: Optical Observations
  39. GRB 030528 (=H2724) Kyoto optical observation
  40. GRB 030416: Optical Observations
  41. GRB 030329 Optical Observations
  42. GRB030329: XMM-Newton observation
  43. GRB 021004: HST observations
  44. GRB030324: Further Observations of the Candidate Optical Afterglow
  45. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  46. IPN triangulation of GRB030519B=H2716 (small error box)
  47. HETE GRB030329, correction to Rc Observations in Loiano
  48. GRB 030329: Optical limit (contemporaneous imaging)
  49. IPN triangulation of GRB030509 (small errror box)
  50. GRB030329, BVRI photometry
  51. GRB030429, refiend optical brightness
  52. GRB 030329: Optical limit (contemporaneous photography)
  53. GRB030418, BVRcIc field photometry
  54. GRB030429, BVRcIc field photometry
  55. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  56. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  57. GRB030329: RTT150 optical observations and upper limit for a host
  58. GRB030501, optical observation
  59. GRB030501 triangulation (correction to GCN 2194)
  60. GRB030329: RTT150 optical observations and upper limit for a host
  61. GRB 030429: redshift from VLT spectroscopy
  62. GRB030501B triangulation (single error box)
  63. GRB 030329, BVRI photometry
  64. GRB030429: Optical Observations
  65. GRB030501: TAROT candidate afterglow present in archival images
  66. GRB 030429: confirmation of afterglow candidate
  67. GRB 030329 Oprical observations in Rozhen observatory
  68. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  69. IPN triangulation of GRB030425 (single error box)
  70. GRB 030329, the review of the sky area in plate archive (1950-1998)
  71. GRB 030329: optical spectropolarimetry at VLT
  72. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  73. GRB030329: optical polarization
  74. IPN triangulation of GRB030422 (two large error boxes)
  75. GRB030329, optical observation
  76. MASTER:optical observations GRB030418
  77. MASTER:optical observations probable GRB030414
  78. GRB030418: Kiso near infrared observations
  79. GRB 030418: Optical afterglow
  80. OT GRB 030329: early UBVRcIc spectral evolution
  81. OT GRB 030329: early spectrum
  82. IPN triangulation of GRB030414 (small error box)
  83. IPN triangulation of GRB030413 (small error box)
  84. Superluminal motion in GRB 030329 (Correction)
  85. Superluminal motion in GRB 030329
  86. GRB030329, optical position
  87. IPN triangulation of GRB030406 (small error box)
  88. IPN triangulation of GRB050403 (small error box)
  89. GRB 030329: BVRI photometry at Asiago
  90. GRB 030329: VLT V-band photometry
  91. Kiso observation of the GRB030329 at April 6
  92. GRB 030329, color evolution
  93. GRB030328, UBVRcIc field photometry
  94. GRB 030329 Optical observations
  95. GRB030329: Kiso B and R band observations
  96. GRB030328: R upper limit after 6 hours by MASTER
  97. SDSS 0.5m PT observations of GRB030329 (correction)
  98. SDSS 0.5m PT observations of GRB030329
  99. GRB030329: final R-band light curve by MASTER
  100. GRB030329, optical observation

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