R3DR, Inside ESA EXPOSE-R, Outside “Zvezda” module of ISS

Satellite provider: ROSCOSMOS
Experiment name: EXPOSE-R
Instrument name: R3DR                          

Cooperation: Bulgaria, Germany
Begin-end of data: 11/03/2009-20/08/2010
PI/CoPI: G. Horneck, DLR; D. Häder, UE; Ts. Dachev, SRTI
Main descr. Reference:
Dachev et al., 2015), http://dx.doi.org/10.1017/S1473550414000093  
 

Units: Size [mm]/Mass [kg]: 1 DU (76x76x36 mm, 0.17 kg)
Place, Shielding [g cm-2]: Outside of ISS, outside Zvezda module, in the EXPOSE-R facility >0.6 g cm-2
Resolution [sec]/[min]: 10 s

External view of EXPOSE-R facility and R3DR instrument

 

External view of R3DR2 instrument.

Block-diagram of RADOM instrument.

 

Dose measurement algorithms and formulas*

The main measured parameter in the R3DR instrument is the amplitude of the pulse after the CSA, generated by a particle or a photon partially or fully crossing the detector (Dachev et al., 2002). The amplitude of the pulse is proportional by a factor of 240mV/MeV to the energy deposited in the detector and to the dose, respectively. These amplitudes are digitized in an 8-bit ADC and organized in a 256-channel deposited energy spectrum.

By definition the dose in the silicon detector DSi [Gy] is one joule deposited in 1 kg of matter. The MDUs absorbed dose is calculated by dividing the summarized energy deposition in the spectrum in joules by the mass of the detector in kilograms:

 

where K is a coefficient. MD is the mass of the detector, and Eli is the energy loss in Joules in channel i. The energy in MeV is proportional to the amplitude A of the pulse: Eli [MeV] =A [V]/0.24 [V/MeV], where 0.24 [V/MeV] is a coefficient dependent on the preamplifier used and its sensitivity.

All 255 deposited dose values, depending on the deposited energy for one exposure period, form the deposited energy spectrum. Channel 256 accumulates all pulses with amplitudes higher than the upper energy of 20.83MeV measured by the spectrometer. The methods for characterization of the type of incoming space radiation are described in Dachev (2009), http://dx.doi.org/10.1016/j.asr.2009.08.007; and Dachev et al. (2017), https://doi.org/10.1002/2016SW001580.

“DATA SOURCES” string description

UT date and time (DD/MM/YYYY hh:mm:ss); A/D; ALT (altitude (km); longitude (deg); latitude (deg); L value; total magnetic field strength B (Gauss); LT (hours); DIPL dip latitude (deg); INVLAT invariant latitude (deg); F flux (1/cm2 s); D absorbed dose rate (µGy/hour); D/F (nGy cm2 particle-1); PE proton energy (MeV); H* total apparent ambient dose equivalent rate H*(10) (µSv/hour), H*l calculated low energy component of H*(10)low (µSv/hour); H*h high energy component of H*(10)high (µSv/hour); ch1-ch255. All files are in csv format.

Link to the full text “DATA SOURCES” files: http://esa-pro.space.bas.bg/datasources/R3DR

Additional references, concerning R3DR data:

Dachev, T.P., B.T. Tomov, Yu.N. Matviichuk, Pl.G. Dimitrov, N.G. Bankov, G. Reitz, G. Horneck, D.-P. Häder, M. Lebert, M. Schuster, Relativistic Electron Fluxes and Dose Rate Variations Observed on the International Space Station, J. Atmospheric and Solar-Terrestrial Physics, 99, 150-156, 2013. http://dx.doi.org/10.1016/j.jastp.2012.07.007

Dachev Ts., Analysis of the space radiation doses obtained simultaneously at 2 different locations outside ISS, Adv. Space Res., 52, 1902-1910, 2013 http://dx.doi.org/10.1016/j.asr.2013.08.011  

Dachev, T.P., Profile of the ionizing radiation exposure between the Earth surface and free space, Journal of Atmospheric and Solar-Terrestrial Physics, 102, September 2013, 148–156, 2013, http://dx.doi.org/10.1016/j.jastp.2013.05.015

Dachev, T., G. Horneck, D.-P. Häder, M. Schuster, and M. Lebert, EXPOSE-R cosmic radiation time profile, Journal of Astrobilogy, 14, 17-25, 2015. http://dx.doi.org/10.1017/S1473550414000093

Dachev, T.P., J.V. Semkova, B.T. Tomov, Yu.N. Matviichuk, Pl.G. S. Maltchev, R. Koleva, Pl., Dimitrov, N.G. Bankov, V.V., Shurshakov, V.V., Benghin, E.N., Yarmanova, O.A. Ivanova, D.-P. Häder, M.T. Schuster, G. Reitz, G. Horneck, Y. Uchihori, H. Kitamura, O. Ploc,  J. Kubancak, I. Nikolaev, Overview of the Liulin type instruments for space radiation measurement and their scientific results, 92–114, 2015. http://dx.doi.org/10.1016/j.lssr.2015.01.005

Please acknowledge data provider:

Tsvetan Dachev, SRTI-BAS: tdachev@bas.bg or: tdachev59@gmail.com

URL: http://scholar.google.com/citations?user=uzmW_mwAAAAJ