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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"

21769 results found.

  1. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  2. IPN triangulation of GRB030606 (two alternate error boxes)
  3. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  4. IPN triangulation of GRB030605B (annulus)
  5. GRB 030528: tentative NIR counterpart
  6. GRB 030528, radio observations
  7. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  8. GRB030329, further radio observations at GMRT
  9. GRB030528, BVRI field photometry
  10. GRB030329, SPM optical observations
  11. GRB030528(=H2724): Revised SXC Localization
  12. GRB 030528 Bisei optical observation
  13. GRB030528 (H2724): A long GRB localized by HETE
  14. GRB 030528 (=H2724) Kyoto optical observation
  15. GRB030329, Optical observations
  16. GRB 030329: HST ACS Observations of the Host
  17. GRB 030329 Optical Observations
  18. GRB030329: XMM-Newton observation
  19. GRB 021004: HST observations
  20. GRB030324: Further Observations of the Candidate Optical Afterglow
  21. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  22. GRB 030418: Second Epoch Optical Observations with Magellan
  23. HETE GRB030329, correction to Rc Observations in Loiano
  24. GRB 030329: Optical limit (contemporaneous imaging)
  25. IPN triangulation of GRB030509 (small errror box)
  26. IPN triangulation of GRB030509 - correction
  27. IPN triangulation of GRB030509 (single error box)
  28. GRB030329: RTT150 optical observations
  29. GRB030329, BVRI photometry
  30. GRB030429, refiend optical brightness
  31. GRB030418, BVRcIc field photometry
  32. GRB 030429: Redshift of neighbor galaxy
  33. GRB030429, BVRcIc field photometry
  34. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  35. GRB030429: RTT150 optical observations, a possible host galaxy
  36. GRB030329: RTT150 optical observations and upper limit for a host
  37. GRB030329: RTT150 optical observations and upper limit for a host
  38. GRB 030429: redshift from VLT spectroscopy
  39. GRB030501: TAROT candidate afterglow present in archival images
  40. GRB 030429: confirmation of afterglow candidate
  41. GRB030425: CrAO optical observation
  42. IPN triangulation of GRB030429 (annulus)
  43. GRB 030329 Oprical observations in Rozhen observatory
  44. GRB 030429: ROTSE-III observations
  45. GRB030329, SPM optical observations
  46. GRB 030329, the review of the sky area in plate archive (1950-1998)
  47. GRB 030329: optical spectropolarimetry at VLT
  48. IPN triangulation of GRB030422C (annulus)
  49. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  50. GRB030329: optical polarization
  51. IPN triangulation of GRB030422 (two large error boxes)
  52. MASTER:optical observations GRB030418
  53. MASTER:optical observations probable GRB030414
  54. ROTSE-III prompt optical detections of GRB 030418
  55. GRB030418: Kiso near infrared observations
  56. OT GRB 030329: early spectrum
  57. GRB030324: Candidate Optical Afterglow
  58. IPN triangulation of GRB030413 (small error box)
  59. GRB030329, optical position
  60. IPN triangulation of GRB030406 (small error box)
  61. IPN triangulation of GRB050403 (small error box)
  62. GRB030329: HET spectroscopic monitoring
  63. Kiso observation of the GRB030329 at April 6
  64. GRB030328, UBVRcIc field photometry
  65. GRB 030329 Optical observations
  66. GRB 030329, color evolution
  67. GRB 030329: possible color change
  68. GRB030329: Kiso B and R band observations
  69. SDSS 0.5m PT observations of GRB030329 (correction)
  70. SDSS 0.5m PT observations of GRB030329
  71. GRB030329: final R-band light curve by MASTER
  72. GRB 030329: Sub-millimeter detection
  73. GRB030329, new UBVRcIc field photometry
  74. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  75. GRB030329: Optical observations at Teramo
  76. GRB 030329: Radio observations at GMRT
  77. GRB 030329: Additional Mt. Laguna Optical Observations
  78. GRB 030329: Observations with ANDICAM
  79. GRB 030329: fitting parameters and re-brightening
  80. triangulation of GRB 030331 (single error box)
  81. AAVSO V & R observations of GRB030329
  82. GRB 030329: optical observations
  83. GRB 030324: Optical and NIR Observations
  84. GRB030329: R band light curve by MASTER
  85. GRB030329 - Light curve flattening
  86. GRB 030324, optical search
  87. GRB 030329, optical observations
  88. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  89. GRB030329a: detection by Konus-Wind
  90. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  91. GRB 030329: Light curve observed during the change of its slope.
  92. GRB030329, BVRcIc field photometry
  93. GRB030329, SPM optical observations
  94. GRB030329 optical observations
  95. GRB 030329: Optical pre-Imaging
  96. GRB 030329: Upper limit from 5.6 hours before trigger
  97. GRB030328: X-ray Afterglow Observed with Chandra
  98. GRB 030329, R-band observations
  99. GRB030329: Upper limits from recent and historical observations.
  100. GRB 030329: Optical Afterglow Observations

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