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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"

24630 results found.

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

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