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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"

38394 results found.

  1. IPN triangulation of GRB030607 (annulus)
  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: Optical Observations
  6. IPN triangulation of GRB030605 (annulus)
  7. GRB 030528: tentative NIR counterpart
  8. GRB 030528, radio observations
  9. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  10. GRB030329, further radio observations at GMRT
  11. GRB030528, BVRI field photometry
  12. IPN triangulation of GRB030601 (annulus)
  13. GRB030329, SPM optical observations
  14. GRB030528: Chandra TOO Planned
  15. MASTER: optical observation GRB030601
  16. GRB030528(=H2724): Revised SXC Localization
  17. GRB 030528, Teramo optical observation
  18. GRB 030528 Bisei optical observation
  19. GRB030528 (H2724): A long GRB localized by HETE
  20. GRB 030329: Correction to GCN 2254
  21. GRB 030329: Optical Observations
  22. GRB 030528: Optical observations at RIKEN
  23. GRB 030528 (=H2724) Kyoto optical observation
  24. IPN triangulation of GRB030523B (annulus)
  25. GRB 030416: Optical Observations
  26. IPN triangulation of GRB030523 (annulus)
  27. GRB030329, Optical observations
  28. GRB 030329: HST ACS Observations of the Host
  29. GRB 030329 Optical Observations
  30. GRB030329: XMM-Newton observation
  31. GRB 021004: HST observations
  32. GRB030324: Further Observations of the Candidate Optical Afterglow
  33. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  34. IPN triangulation of GRB030519B=H2716 (small error box)
  35. GRB 030418: Second Epoch Optical Observations with Magellan
  36. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  37. IPN triangulation of GRB030519 (annulus)
  38. IPN triangulation of GRB030518C (annulus)
  39. IPN triangulation of GRB030518B (annulus)
  40. IPN triangulation of GRB030518A (annulus)
  41. IPN triangulation of GRB030514 (annulus)
  42. IPN triangulation of GRB030513 (annulus)
  43. IPN triangulation of GRB030509B (annulus)
  44. GRB 030329: Optical limit (contemporaneous imaging)
  45. GRB 030501: final TAROT limits
  46. IPN triangulation of GRB030509 (small errror box)
  47. IPN triangulation of GRB030509 - correction
  48. IPN triangulation of GRB030509 (single error box)
  49. GRB030329: RTT150 optical observations
  50. GRB030329, BVRI photometry
  51. GRB030429, refiend optical brightness
  52. GRB 030329: Optical limit (contemporaneous photography)
  53. GRB030418, BVRcIc field photometry
  54. GRB 030429: Redshift of neighbor galaxy
  55. GRB030429, BVRcIc field photometry
  56. GRB 030329: High-Resolution Spectroscopy of the Host
  57. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  58. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  59. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  60. GRB030429: RTT150 optical observations, a possible host galaxy
  61. IPN triangulation of GRB030506 (annulus)
  62. IPN triangulation of GRB030505B (large error box)
  63. IPN triangulation of GRB030505A (annulus)
  64. GRB030329: RTT150 optical observations and upper limit for a host
  65. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  66. GRB030501, optical observation
  67. GRB030501C triangulation (annulus)
  68. GRB030501 triangulation (correction to GCN 2194)
  69. GRB030329: RTT150 optical observations and upper limit for a host
  70. GRB 030429: Radio Observations
  71. GRB 030429: redshift from VLT spectroscopy
  72. GRB 030429: IR photometry with IRSF/SIRIUS
  73. GRB030501B triangulation (single error box)
  74. GRB030328, optical observation
  75. GRB 030329, BVRI photometry
  76. GRB 030501: TAROT possible candidate counterpart
  77. IPN triangulation of GRB030501 (IBIS event; annulus)
  78. IPN triangulation of GRB030501B (annulus)
  79. GRB 030429: confirmation of afterglow candidate
  80. GRB030429, possible optical counterpart
  81. GRB030501 localized by INTEGRAL
  82. GRB030425: CrAO optical observation
  83. IPN triangulation of GRB030429 (annulus)
  84. IPN triangulation of GRB030428 (two large error boxes)
  85. GRB 030329 Oprical observations in Rozhen observatory
  86. GRB 030429: ROTSE-III observations
  87. GRB 030324: Radio Observations
  88. GRB030329 observed as a sudden ionospheric disturbance (SID)
  89. IPN triangulation of GRB030426 (annulus)
  90. IPN triangulation of GRB030425 (single error box)
  91. GRB 030329, the review of the sky area in plate archive (1950-1998)
  92. GRB 030329: Spectral Evolution of SN 2003dh
  93. Optical Observations of GRB 030418 with Magellan
  94. GRB 030329: optical spectropolarimetry at VLT
  95. IPN triangulation of GRB030422C (annulus)
  96. IPN triangulation of GRB030422B (annulus)
  97. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  98. GRB030329: optical polarization
  99. IPN triangulation of GRB030422 (two large error boxes)
  100. GRB 030329 3.5 and 6 cm radio observations at RTF-32 telescope

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