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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"

28038 results found.

  1. IPN triangulation of GRB030801 (large error box)
  2. GRB021206 optical counterpart upper limit
  3. IPN triangulation of GRB030726 (large error box)
  4. IPN triangulation of GRB030721 (large error box)
  5. XRF030723 Radio Observations
  6. XRF 030723: confirmation of fading optical counterpart
  7. XRF030723(=H2777): Chandra Observations
  8. GRB030723: Upper limits from historical observations
  9. XRF030723: Palomar observations and proposed counterpart
  10. GRB030725 (=H2779): A Bright GRB Localized by HETE
  11. XRF030723 (= H2777): Chandra Observations Scheduled
  12. XRF030723, BVRcIc field photometry correction
  13. XRF030723, ROTSE-III Early Observations
  14. XRF030723, BVRcIc field photometry
  15. XRF 030723, optical observations
  16. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  17. Konus-Wind detection of the bursts from SGR1806-20 region
  18. SGR 1806-20, submm observations
  19. RXTE PCA Observations of SGR1806-20 Region
  20. IPN triangulation of GRB030714 (two large error boxes)
  21. IPN triangulation of GRB030715 (two large error boxes)
  22. GRB030706 triangulation (single large error box)
  23. GRB030329, optical observation in May
  24. IPN triangulation of GRB030626 (single large error box)
  25. IPN triangulation of GRB030626 (two large error boxes)
  26. GRB030329: second XMM-Newton observation
  27. GRB030329 -- RATAN-600 data in April-May
  28. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  29. IPN triangulation of GRB030606 (two alternate error boxes)
  30. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  31. GRB 030528: tentative NIR counterpart
  32. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  33. GRB030528, BVRI field photometry
  34. GRB030329, SPM optical observations
  35. GRB030528: Chandra TOO Planned
  36. GRB030528(=H2724): Revised SXC Localization
  37. GRB 030528 Bisei optical observation
  38. GRB030528 (H2724): A long GRB localized by HETE
  39. GRB 030329: Correction to GCN 2254
  40. GRB 030329: Optical Observations
  41. GRB 030528 (=H2724) Kyoto optical observation
  42. GRB 030416: Optical Observations
  43. GRB 030329 Optical Observations
  44. GRB030329: XMM-Newton observation
  45. GRB 021004: HST observations
  46. GRB030324: Further Observations of the Candidate Optical Afterglow
  47. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  48. IPN triangulation of GRB030519B=H2716 (small error box)
  49. HETE GRB030329, correction to Rc Observations in Loiano
  50. GRB 030329: Optical limit (contemporaneous imaging)
  51. IPN triangulation of GRB030509 (small errror box)
  52. GRB030329, BVRI photometry
  53. GRB030429, refiend optical brightness
  54. GRB 030329: Optical limit (contemporaneous photography)
  55. GRB030418, BVRcIc field photometry
  56. GRB030429, BVRcIc field photometry
  57. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  58. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  59. GRB030329: RTT150 optical observations and upper limit for a host
  60. GRB030501, optical observation
  61. GRB030501 triangulation (correction to GCN 2194)
  62. GRB030329: RTT150 optical observations and upper limit for a host
  63. GRB 030429: redshift from VLT spectroscopy
  64. GRB030501B triangulation (single error box)
  65. GRB 030329, BVRI photometry
  66. GRB030429: Optical Observations
  67. GRB030501: TAROT candidate afterglow present in archival images
  68. GRB 030429: confirmation of afterglow candidate
  69. GRB 030329 Oprical observations in Rozhen observatory
  70. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  71. IPN triangulation of GRB030425 (single error box)
  72. GRB 030329, the review of the sky area in plate archive (1950-1998)
  73. GRB 030329: optical spectropolarimetry at VLT
  74. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  75. GRB030329: optical polarization
  76. IPN triangulation of GRB030422 (two large error boxes)
  77. GRB030329, optical observation
  78. MASTER:optical observations GRB030418
  79. MASTER:optical observations probable GRB030414
  80. GRB030418: Kiso near infrared observations
  81. GRB 030418: Optical afterglow
  82. OT GRB 030329: early UBVRcIc spectral evolution
  83. OT GRB 030329: early spectrum
  84. IPN triangulation of GRB030414 (small error box)
  85. IPN triangulation of GRB030413 (small error box)
  86. Superluminal motion in GRB 030329 (Correction)
  87. Superluminal motion in GRB 030329
  88. GRB030329, optical position
  89. IPN triangulation of GRB030406 (small error box)
  90. IPN triangulation of GRB050403 (small error box)
  91. GRB 030329: BVRI photometry at Asiago
  92. GRB 030329: VLT V-band photometry
  93. Kiso observation of the GRB030329 at April 6
  94. GRB 030329, color evolution
  95. GRB030328, UBVRcIc field photometry
  96. GRB 030329 Optical observations
  97. GRB030329: Kiso B and R band observations
  98. GRB030328: R upper limit after 6 hours by MASTER
  99. SDSS 0.5m PT observations of GRB030329 (correction)
  100. SDSS 0.5m PT observations of GRB030329

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