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HEND, the High Energy Neutron Detector, provides the first results of detecting high energy neutrons on Mars. It measures the flux and energy spectra of Martian neutrons, providing valuable information about the subsurface composition of the "red planet". The mapping of Martian neutrons could greatly contribute to our understanding of the local and global hydrological evolution of Mars, and should be considered in future space missions for Mars studies and exploration.
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HEND: High Energy Neutron Detector The first results of Russian High Energy Neutron Detector I.Mitrofanov HEND Workshop 2002 IKI, Moscow May 20, 2002
HEND: High Energy Neutron Detector PHYSICS: Galactic Cosmic Rays freely propagates through thin Martian atmosphere and produce neutrons, gamma-rays and X-rays in the 2-3 meters subsurface layer Their flux and energy spectra manifest the elementary composition of the “red planet” subsurface
HEND: High Energy Neutron Detector MAIN TASK of HEND: To measure flux and energy spectra of Martian neutrons for interpretation of nuclear lines from Gamma-Ray Spectrometer
HEND: High Energy Neutron Detector HEND has three detectors of neutrons based on proportional counters 3Hewith thick (LD), medium (MD) and thin (SD) moderators, one scintillation detector for fast neutrons IN/SC and detector for anti-coincidence OUT/SC HEND was designed for detection of high energy neutrons from the Martian surface
HEND: High Energy Neutron Detector • PERFORMANCE: • LD:10.0 eV- 1.0 MeV • MD:0.4 eV-100.0 keV • SD:0.4 eV- 1.0 keV • IN/SC/N: 850 keV – 15.0 MeV • IN/SC/G:60 keV– 2.0 MeV • OUT/SC:30 keV – 1.0 MeV
HEND: High Energy Neutron Detector September 2000 December 1999 The development of HEND took place in 1998-2001 in RosAviaKosmos IKI SDB of IKI SNIIP JINR IMB VIMS PTIDD UofA NASA JPL LMA NASA KSC April 7, 2001 February 19, 2001
HEND: High Energy Neutron Detector Odyssey arrived to Mars on October 24, 2001
HEND: High Energy Neutron Detector FIRST GAMMA-RAYS from Mars: “Phobos-2” February 1-11, 1989
HEND: High Energy Neutron Detector FIRST NEUTRONS From Mars: «Odyssey» October 25-26, 2001
HEND: High Energy Neutron Detector Present global map of Mars landscape is made by famous Mars Orbital Laser Altimeter on board NASA Mars Global Surveyor
HEND: High Energy Neutron Detector Present global map of Mars neutron emission is made by High Energy Neutron Detector on board NASA Mars Global Surveyor (50 days data of sensor MD for epithermal neutrons 0.4 eV – 100 keV)
HEND: High Energy Neutron Detector There is perfect agreement between maps from HEND (top) and Neutron Spectrometer (bottom)
HEND: High Energy Neutron Detector HEND map from Stilbene Sensor: 50 days, 5ºx5º, 850 keV – 2 MeV, peak flux is 0.17 cts/s
HEND: High Energy Neutron Detector HEND map from Stilbene Sensor: 50 days, 5ºx5º, 3 MeV – 7 MeV, peak flux is 0.12 cts/s
HEND: High Energy Neutron Detector CONCLUSIONS: The mapping of Martian neutrons could provide the most important knowledge for models of local and global hydrological evolution of Mars The neutrons maps should be taken into account in future space missions for Mars studies and exploration