DESCRIPTION OF THE DOK-2 EXPERIMENT
(TAIL AND AURORAL PROBES, INTERBALL PROJECT)

The goal of the DOK-2 experiment (Russia, Slovakia, Greece) of the INTERBALL project was to measure energetic electron and ion spectra in the Earth's magnetosphere.

Instrument description and main publications:

  1. V.N. Lutsenko, K. Kudela, and E.T. Sarris, The DOK-2 Experiment to Study Energetic Particles by the Tail Probe and Auroral Probe Satellites in the INTERBALL Project.
    Cosmic Research, 36, 1, 93-102, 1998. PDF
  2. V.N. Lutsenko, K. Kudela, Almost monoenergetic ions near the Earth's magnetosphere boundaries.
    GEOPHYSICAL RESEARCH LETTERS, 26, 3, 413-416, 1999. PDF
  3. V.N. Lutsenko, Almost monoenergetic ions: New support for Alfven ideas on the role of electric currents in space plasmas?
    Physics and Chemistry of the Earth, Part C: Solar,Terrestrial and Planetary Science, 26, 8, 615-619, 2001. PDF
  4. V.N. Lutsenko, V.N., Gretchko, T.V., Kobelev, A.V., and K. Kudela, Dispersion Structures in the Energetic Ion and Electron Spectra in the Auroral Regions: Their Nature, Properties and Implication.
    Adv. Sp. Res. vol. 30, No 7, pp. 1787-1792, Nov. 2002. PDF
  5. V.N. Lutsenko, I.P. Kirpichev, T.V. Grechko, D. Delcourt, Source positions of energetic particles responsible for the fine dispersion structures: numerical simulation results.
    Planetary and Space Science, 53, 275–281, 2005. PDF

Energy and time resolution.


The DOK-2 instrument has 2 pairs of energetic particle telescopes (semiconductor detectors). One detector in each pair counts electrons, (1e,2e) another - ions (1p,2p). Energy spectrum is taken at 55 energy levels in the range 20-400 keV for electrons and at 56 levels in the range 20-800 keV for ions. Exact energy tables vary from detector to detector and are listed below. Count accumulation time is flexible and depends on a count rate. Time of measurement corresponds to end of accumulation interval. Duration of measurement is always provided in a special variable. In some modes it can be substantially different from the period elapsed from the previous measurement.
To provide faster measurements from each telescope besides spectra three "time-profile" (TP) parameters are determined as counts in wider energy ranges (a sum of four spectral levels) and transmitted with generally smaller accumulation time (than that of spectra). See energy tables below.
DOK-2 onboard auroral probe had special real-time operation mode (STO) which provided fast measurements of particle fluxes (generally of the order of 1 sec) in short time intervals in seven integral energy ranges (each is a sum of several spectral levels). See energy tables below. The accumulation time is fixed in this mode and is not given as a separate variable. Originally for this mode measurements are performed seevral times per second, but this dataset contains 2-sec or 4-sec averages in order to increase statistical significance.
Noise background levels (spectra measured at very low energetic particle intensities are rather low and substracted.

Sensor attitude.


The 1-st pair of telescopes (1e, 1p) was directed at 180 deg (antisunward) to the satellite spin axis. For the 2-nd pair (2e, 2p) this angle can be set by commands to 45, 90, 135 or 180 deg or can change continuously from 45 to 180 deg in the scanning mode. All measurements of Auroral instrument were performed at 79 deg. All measurements of Tail instrument after September 1995 were performed at 62 deg. Information on telescope pointing is contained in "theta" variable. The second angle (azimuthal pointing in spacecraft spin frame) is meaningful only when count accumulation time is substantially less than spacecraft spin period (120 sec) and has to be computed using spacecraft attitude data. Instrument pointing onboard is 15 deg from +Y axis (towards +Z).

Data availability.


Onboard the Tail Probe 2e-telescope worked normally from the mission start (5.08.95) to 11.09.95 18:50 UT, then from 31.12.95 07:01:44 UT to 28.02.96 17:25 UT, 3.02.97 from 15:30 to 15:40 UT and 18.02.97 from 20:30 to 21:16 UT. The 1e, 1p and 2p-telescopes worked normally till the end of mission. On the Auroral probe shortly after the mission startn the 1e detector noise increased and data should be treated with caution after 21.03.97. Noise of other telescopes increased significantly after April 1998 due to radiation damage and the data after this time were not processed. Data for switched-off telescopes or blocked in the overload mode are zeros.

Experiment data include:

  1. Interball Key Parameters (2-min data of "time-profile" channells).
  2. Interball Key Parameters daily plots.
  3. Tail probe 6-hour plots of full resolution spectrograms and "time-profile" parameters.
  4. Auroral probe STO real-time session quick-look plots.
  5. Full digital data including Auroral and Tail probe full spectra, time-profile parameters (to be available later) and STO real-time data.

All questions should be addressed to V.N. Lutsenko: vlutsenk@iki.rssi.ru

DOK-2 energy tables

Tail Probe spectra energies  (Emin Emax, keV).

Chan#   1e(1)            2e(2)            1p(3)            2p(4)
1       27.46 28.22      26.68 27.38      21.04 22.39      20.07 21.40
2       28.21 29.04      27.38 28.14      22.40 23.82      21.40 22.82
3       29.04 29.98      28.15 28.99      23.82 25.30      22.82 24.29
4       29.98 30.96      28.98 29.93      25.30 26.89      24.29 25.85
5       30.95 32.00      29.93 30.92      26.89 28.59      25.85 27.53
6       32.01 33.15      30.92 31.99      28.59 30.42      27.53 29.33
7       33.15 34.38      31.99 33.15      30.42 32.39      29.33 31.28
8       34.37 35.69      33.15 34.40      32.39 34.48      31.28 33.37
9       35.70 37.12      34.40 35.75      34.48 36.69      33.37 35.57
10      37.12 38.63      35.75 37.20      36.69 39.06      35.57 37.92
11      38.63 40.23      37.21 38.75      39.06 41.63      37.92 40.46
12      40.23 41.88      38.75 40.38      41.63 44.36      40.46 43.22
13      41.88 43.68      40.38 42.07      44.36 47.21      43.21 46.08
14      43.68 45.63      42.07 43.92      47.21 50.26      46.09 49.15
15      45.63 47.79      43.92 45.93      50.26 53.51      49.15 52.42
16      47.79 50.11      45.94 48.17      53.51 57.02      52.42 55.95
17      50.11 52.55      48.17 50.55      57.03 60.81      55.95 59.75
18      52.55 55.16      50.55 53.07      60.81 64.86      59.74 63.86
19      55.16 57.93      53.07 55.76      64.85 69.11      63.86 68.17
20      57.94 60.88      55.76 58.62      69.11 73.64      68.17 72.77
21      60.87 63.97      58.62 61.64      73.64 78.57      72.77 77.77
22      63.97 67.34      61.64 64.86      78.56 83.85      77.77 83.16
23      67.34 70.93      64.87 68.38      83.85 89.48      83.15 88.90
24      70.94 74.74      68.37 72.08      89.48 95.50      88.90 95.06
25      74.74 78.81      72.09 76.05      95.50 101.93     95.06 101.66
26      78.81 83.12      76.05 80.27     101.94 108.78    101.66 108.68
27      83.11 87.69      80.27 84.74     108.77 116.13    108.68 116.25
28      87.69 92.53      84.74 89.51     116.13 124.04    116.24 124.40
29      92.54 97.71      89.52 94.56     124.04 132.55    124.40 133.19
30      97.71 103.02     94.56 99.98     132.55 141.69    133.19 142.65
31      03.02 108.75     99.98 105.47    141.70 151.48    142.65 152.76
32     108.75 114.89    105.46 111.48    151.47 161.83    152.76 163.53
33     114.90 121.47    111.48 117.93    161.83 172.99    163.54 175.16
34     121.47 128.49    117.94 124.85    172.99 185.00    175.16 187.68
35     128.49 135.98    124.84 132.22    184.98 197.86    187.68 201.13
36     135.98 143.95    132.22 140.09    197.87 211.55    201.13 215.44
37     143.95 152.31    140.10 148.49    211.54 226.24    215.45 230.89
38     152.31 161.09    148.48 157.15    226.24 242.04    230.89 247.51
39     161.09 170.46    157.15 166.43    242.05 258.92    247.51 265.24
40     170.46 180.44    166.43 176.33    258.91 276.98    265.24 284.34
41     180.43 191.04    176.33 186.88    276.98 296.39    284.34 304.84
42     191.05 202.26    186.87 198.09    296.40 317.11    304.84 326.80
43     202.25 214.09    198.09 209.86    317.10 339.34    326.80 350.43
44     214.09 226.68    209.86 222.41    339.35 363.14    350.43 375.71
45     226.69 240.07    222.42 235.77    363.14 388.65    375.71 402.91
46     240.06 254.22    235.77 249.96    388.65 415.94    402.91 432.05
47     254.22 269.18    249.96 264.92    415.94 445.21    432.05 463.34
48     269.19 285.10    264.92 280.85    445.21 476.51    463.34 496.94
49     285.09 301.90    280.85 297.78    476.51 510.06    496.93 532.95
50     301.91 319.81    297.79 315.69    510.06 546.00    532.95 571.58
51     319.81 338.78    315.69 334.76    546.00 584.44    571.58 612.87
52     338.78 358.90    334.76 355.03    584.44 625.25    612.87 656.90
53     358.91 380.15    355.04 376.41    625.25 669.03    656.91 704.64
54     380.14 402.67    376.41 399.16    669.03 716.35    704.64 756.23
55     402.67 426.56    399.16 423.24    716.34 767.35    756.23 811.45
56     																	 767.34 821.49    811.45 869.87

Auroral Probe spectra energies  (Emin Emax, keV).

Chan#   1e(1)            2e(2)            1p(3)            2p(4)
1       25.10 25.68      24.79 25.33      17.32 18.41      18.49 19.70
2       25.68 26.31      25.33 25.92      18.41 19.56      19.71 21.05
3       26.31 27.01      25.93 26.58      19.56 20.82      21.05 22.49
4       27.01 27.78      26.58 27.30      20.82 22.17      22.48 23.99
5       27.78 28.63      27.30 28.09      22.17 23.60      24.00 25.59
6       28.63 29.57      28.09 28.96      23.60 25.08      25.58 27.29
7       29.57 30.61      28.96 29.95      25.08 26.67      27.29 29.13
8       30.61 31.71      29.95 30.99      26.67 28.37      29.13 31.12
9       31.71 32.91      30.99 32.12      28.37 30.20      31.12 33.26
10      32.91 34.21      32.11 33.33      30.20 32.18      33.26 35.52
11      34.20 35.61      33.33 34.65      32.18 34.28      35.53 37.96
12      35.61 37.13      34.66 36.09      34.28 36.50      37.95 40.57
13      37.13 38.75      36.09 37.63      36.49 38.87      40.58 43.43
14      38.75 40.47      37.64 39.28      38.87 41.45      43.43 46.40
15      40.47 42.26      39.28 41.00      41.45 44.20      46.40 49.58
16      42.27 44.24      41.00 42.83      44.20 47.07      49.58 52.99
17      44.24 46.40      42.83 44.84      47.07 50.14      52.98 56.67
18      46.40 48.79      44.83 47.04      50.14 53.42      56.67 60.65
19      48.79 51.33      47.04 49.46      53.42 56.96      60.65 64.94
20      51.33 54.05      49.46 52.02      56.96 60.77      64.94 69.47
21      54.05 56.95      52.03 54.78      60.77 64.85      69.47 74.31
22      56.95 60.06      54.77 57.70      64.85 69.15      74.31 79.60
231     60.06 63.32      57.70 60.82      69.15 73.73      79.60 85.29
24      63.32 66.88      60.82 64.12      73.73 78.71      85.29 91.37
25      66.88 70.71      64.12 67.72      78.71 84.06      91.37 97.91
26      70.71 74.78      67.72 71.57      84.06 89.76      97.91 104.90
27      74.78 79.15      71.57 75.67      89.76 95.86     104.90 112.40
28      79.15 83.79      75.67 80.07      95.86 102.38    112.39 120.50
29      83.79 88.76      80.07 84.74     102.38 109.32    120.50 129.26
30      88.76 94.03      84.74 89.73     109.32 116.79    129.26 138.71
31      94.03 99.70      89.73 95.02     116.79 124.83    138.71 148.90
32      99.70 105.48     95.02 100.67    124.83 133.48    148.90 159.71
33     105.48 111.83    100.67 106.50    133.49 142.79    159.70 171.38
34     111.83 118.66    106.50 112.88    142.79 152.72    171.39 184.01
35     118.66 126.00    112.88 119.73    152.71 163.27    184.00 197.61
36     126.00 133.86    119.73 127.08    163.27 174.65    197.61 212.12
37     133.86 142.28    127.09 134.97    174.65 186.89    212.12 227.78
38     142.28 151.20    134.97 143.40    186.90 200.05    227.79 244.70
39     151.21 160.53    143.39 152.27    200.04 213.99    244.69 262.78
40     160.53 170.55    152.27 161.62    214.00 229.03    262.79 282.29
41     170.55 181.27    161.62 171.64    229.03 245.20    282.29 303.29
42     181.28 192.73    171.64 182.35    245.20 262.44    303.29 325.82
43     192.73 204.85    182.35 193.79    262.43 280.95    325.82 350.13
44     204.85 217.74    193.79 205.87    280.95 300.84    350.13 376.19
45     217.74 231.51    205.87 218.73    300.84 322.07    376.19 404.28
46     231.51 246.19    218.73 232.46    322.07 344.90    404.27 434.44
47     246.19 261.74    232.46 247.09    344.90 369.31    434.44 466.89
48     261.74 278.32    247.08 262.56    369.31 395.53    466.89 501.82
49     278.32 296.01    262.57 279.08    395.53 423.57    501.82 539.35
50     296.01 314.77    279.08 296.68    423.57 453.67    539.35 579.68
51     314.77 334.82    296.67 315.33    453.67 485.90    579.68 622.73
52     334.82 356.19    315.33 335.26    485.90 520.44    622.73 669.03
53     356.19 378.81    335.26 356.49    520.44 557.46    669.02 719.29
54     378.81 402.91    356.49 378.95    557.46 597.16    719.30 773.71
55     402.91 428.57    378.95 402.87    597.16 639.09    773.71 831.51
56     																	 639.09 684.45    831.50 893.57


Tail Probe timeprofile energies (Emin Emax, keV).

parameter   TP1	       	TP2	       	TP3
chan. used  2-5         14-17        26-29
1e(1)       28.21 32.00 43.68 52.55  78.81 97.71
2e(2)       27.38 30.92 42.07 50.55  76.05 94.56
1p(3)       22.40 28.59 47.21 60.81 101.94 132.55
2p(4)       21.40 27.53 46.09 59.75 101.66 133.19

Auroral Probe timeprofile energies (Emin Emax, keV).

parameter   TP1	       	TP2	       	TP3
chan. used  2-5         14-17       26-29
1e(1)       25.68 28.63 38.75 46.40 70.71 88.76
2e(2)       25.33 28.09 37.64 44.84 67.72 84.74
1p(3)       18.41 23.60 38.87 50.14 84.06 109.32
2p(4)       19.71 25.59 43.43 56.67 97.91 129.26

Auroral Probe STO energies

detector 1e (1)

#  chan.  Emin  Emax
   used   keV   keV
1	  1-8	 25.1    31.71
2	 9-16	 31.71   44.24
3	17-24	 44.24	 66.88
4	25-32	 66.88	105.78
5	33-40	105.78	170.55
6	41-48	170.55	278.32
7	49-56	278.32	455.6

detector 2e (2)

#  chan.  Emin  Emax
   used   keV   keV
1	 1-8	 24.79	 30.99
2	 9-16	 30.99	 42.83
3	17-24	 42.83	 64.12
4	25-32	 64.12	100.67
5	33-40	100.67	161.62
6	41-48	161.62	262.57
7	49-56	262.57	427.9

detector 1p (3)

#  chan.  Emin  Emax
   used   keV   keV
1	  1-8	 17.32	 28.37
2	 9-16	 28.37	 47.07
3	17-24	 47.07	 78.71
4	25-32	 78.71	133.49
5	33-40	133.49	229.03
6	41-48	229.03	395.53
7	49-56	395.53	684.45

detector 2p (4)

#  chan.  Emin  Emax
   used   keV   keV

1	 1-8	 18.49	 31.12
2	 9-16	 31.12	 52.98
3	17-24	 52.98	 91.37
4	25-32	 91.37	159.7
5	33-40	159.7   282.29
6	41-48	282.29	501.82
7	49-56	501.82	893.58