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Flux levels of the PICNIC Camera at IOTA

(this document as PS or PDF)

Sam Ragland dated on 18th Dec. 2003

 

The flux levels of the PICNIC camera at IOTA are characterized in the H band from data taken on 07 Dec. 2003. Four calibrators of spectral type between early B type and late K type are used. The readout mode adopted for these observations is 1 Loop and 4 Reads.

 

Fig. 1 shows observed PICNIC outputs as a function of H magnitude for 1 Loop and 4 Reads. While taking one telescope data, shutters corresponding to the other two telescope beams are closed. Also, background light levels are taken into account. The values reported here are the average values of the four pixels illuminated by each telescope.

 

Assuming that the PICNIC has a linear response over its dynamical range, the expected fluxes for different Loops and Reads, and for a range of H magnitudes are estimated and listed in Table 1. The integration times for various readout modes are taken from Pedretti et al., 2003.

Fig.1: The PICNIC output (ADU) in H band, for the readout mode of 1 Loop and 4 Reads, is plotted against H magnitude for all three telescopes. A straight line fit with a slope of -0.4 is also shown here.

 

H mag

1L1R

1L2R

1L3R

1L4R

1L5R

1L6R

1L7R

H mag

2L1R

2L2R

2L3R

2L4R

2L5R

2L6R

2L7R

1.0

149

 

 

 

 

 

 

1.0

 

 

 

 

 

 

 

1.5

94

141

185

 

 

 

 

1.5

182

 

 

 

 

 

 

2.0

59

89

117

145

174

 

 

2.0

115

172

 

 

 

 

 

2.5

37

56

74

91

110

127

143

2.5

73

109

145

180

 

 

 

3.0

24

35

46

58

69

80

90

3.0

46

69

92

114

137

159

182

3.5

15

22

29

36

44

51

57

3.5

29

43

58

72

86

101

115

4.0

9

14

18

23

28

32

36

4.0

18

27

36

45

54

63

73

4.5

6

9

12

14

17

20

23

4.5

11

17

23

29

34

40

46

5.0

4

6

7

9

11

13

14

5.0

7

11

15

18

22

25

29

5.5

2

4

5

6

7

8

9

5.5

5

7

9

11

14

16

18

6.0

 

2

3

4

4

5

6

6.0

3

4

6

7

9

10

12

6.5

 

 

2

2

3

3

4

6.5

2

3

4

5

5

6

7

7.0

 

 

 

 

2

2

2

7.0

 

2

2

3

3

4

5

H mag

3L1R

3L2R

3L3R

3L4R

3L5R

3L6R

3L7R

H mag

4L1R

4L2R

4L3R

4L4R

4L5R

4L6R

4L7R

2.0

171

 

 

 

 

 

 

2.0

 

 

 

 

 

 

 

2.5

108

162

 

 

 

 

 

2.5

143

 

 

 

 

 

 

3.0

68

102

136

170

 

 

 

3.0

90

135

181

 

 

 

 

3.5

43

64

86

107

129

150

172

3.5

57

85

114

143

171

 

 

4.0

27

41

54

68

81

95

108

4.0

36

54

72

90

108

126

144

4.5

17

26

34

43

51

60

68

4.5

23

34

45

57

68

80

91

5.0

11

16

22

27

32

38

43

5.0

14

21

29

36

43

50

57

5.5

7

10

14

17

20

24

27

5.5

9

14

18

23

27

32

36

6.0

4

6

9

11

13

15

17

6.0

6

9

11

14

17

20

23

6.5

3

4

5

7

8

9

11

6.5

4

5

7

9

11

13

14

7.0

2

3

3

4

5

6

7

7.0

2

3

5

6

7

8

9

7.5

 

2

2

3

3

4

4

7.5

 

2

3

4

4

5

6

8.0

 

 

 

2

2

2

3

8.0

 

 

2

2

3

3

4

H mag

5L1R

5L2R

5L3R

5L4R

5L5R

5L6R

5L7R

H mag

6L1R

6L2R

6L3R

6L4R

6L5R

6L6R

6L7R

2.5

178

 

 

 

 

 

 

2.5

 

 

 

 

 

 

 

3.0

112

169

 

 

 

 

 

3.0

134

 

 

 

 

 

 

3.5

71

107

143

178

 

 

 

3.5

84

128

171

 

 

 

 

4.0

45

67

90

113

135

158

181

4.0

53

81

108

135

162

189

 

4.5

28

42

57

71

85

100

114

4.5

34

51

68

85

102

119

137

5.0

18

27

36

45

54

63

72

5.0

21

32

43

54

65

75

86

5.5

11

17

23

28

34

40

45

5.5

13

20

27

34

41

47

54

6.0

7

11

14

18

21

25

29

6.0

8

13

17

21

26

30

34

6.5

4

7

9

11

14

16

18

6.5

5

8

11

13

16

19

22

7.0

3

4

6

7

9

10

11

7.0

3

5

7

9

10

12

14

7.5

2

3

4

4

5

6

7

7.5

2

3

4

5

6

8

9

8.0

 

2

2

3

3

4

5

8.0

 

2

3

3

4

5

5

H mag

7L1R

7L2R

7L3R

7L4R

7L5R

7L6R

7L7R

H mag

7L1R

7L2R

7L3R

7L4R

7L5R

7L6R

7L7R

3.0

156

 

 

 

 

 

 

6.0

10

15

20

25

30

35

40

3.5

98

149

199

 

 

 

 

6.5

6

9

13

16

19

22

25

4.0

62

94

126

157

189

 

 

7.0

4

6

8

10

12

14

16

4.5

39

59

79

99

119

139

159

7.5

2

4

5

6

8

9

10

5.0

25

37

50

63

75

88

100

8.0

2

2

3

4

5

6

6

5.5

16

24

32

40

47

55

63

8.5

 

 

2

2

3

3

4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 1: The expected PICNIC output in H band for each telescope as a function of H magnitude and readout modes.

 

 

 

Since K magnitudes are more easily available in the literature than H magnitude, the expected PICNIC outputs are also given as a function of K magnitudes (Fig.2 & Table 2). Although color corrections are not applied here, the straight line fit suggests that this calibration is probably not very sensitive to the spectral type of the target (note that stars of different spectral type ranging from early B type to late K type are used for this calibration).

 

The Zero H-magnitude flux is 925 ADU for 1 loop and 4 reads and the Zero K-magnitude flux is 838 ADU for 1 loop and 4 reads. Note that the zero magnitude flux are only for calculation purposes and the PICNIC would saturate around H=1.5 for 1 loop and 4 reads.

 

 

Fig.2: The PICNIC output (ADU) in H band, for the readout mode of 1 loop and 4 reads, is plotted against K magnitude for all three telescopes. A straight line fit with a slope of -0.4  is shown here.

 

 

 

 

K mag

1L1R

1L2R

1L3R

1L4R

1L5R

1L6R

1L7R

K mag

2L1R

2L2R

2L3R

2L4R

2L5R

2L6R

2L7R

1.0

136

 

 

 

 

 

 

1.0

 

 

 

 

 

 

 

1.5

86

128

169

 

 

 

 

1.5

166

 

 

 

 

 

 

2.0

54

81

106

132

159

 

 

2.0

105

157

 

 

 

 

 

2.5

34

51

67

83

100

116

130

2.5

66

99

132

164

 

 

 

3.0

21

32

42

52

63

73

82

3.0

42

63

83

104

125

145

166

3.5

14

20

27

33

40

46

52

3.5

26

39

53

65

79

92

105

4.0

9

13

17

21

25

29

33

4.0

17

25

33

41

50

58

66

4.5

5

8

11

13

16

18

21

4.5

10

16

21

26

31

37

42

5.0

3

5

7

8

10

12

13

5.0

7

10

13

16

20

23

26

5.5

2

3

4

5

6

7

8

5.5

4

6

8

10

12

15

17

6.0

 

2

3

3

4

5

5

6.0

3

4

5

7

8

9

10

6.5

 

 

2

2

3

3

3

6.5

2

2

3

4

5

6

7

7.0

 

 

 

 

2

2

2

7.0

 

2

2

3

3

4

4

K mag

3L1R

3L2R

3L3R

3L4R

3L5R

3L6R

3L7R

K mag

4L1R

4L2R

4L3R

4L4R

4L5R

4L6R

4L7R

2.0

156

 

 

 

 

 

 

2.0

 

 

 

 

 

 

 

2.5

98

147

 

 

 

 

 

2.5

130

 

 

 

 

 

 

3.0

62

93

124

155

 

 

 

3.0

82

123

165

 

 

 

 

3.5

39

59

78

98

118

137

157

3.5

52

78

104

130

156

 

 

4.0

25

37

49

62

74

87

99

4.0

33

49

66

82

99

115

132

4.5

16

23

31

39

47

55

62

4.5

21

31

41

52

62

73

83

5.0

10

15

20

25

30

34

39

5.0

13

20

26

33

39

46

52

5.5

6

9

12

15

19

22

25

5.5

8

12

17

21

25

29

33

6.0

4

6

8

10

12

14

16

6.0

5

8

10

13

16

18

21

6.5

2

4

5

6

7

9

10

6.5

3

5

7

8

10

12

13

7.0

2

2

3

4

5

5

6

7.0

2

3

4

5

6

7

8

7.5

 

 

2

2

3

3

4

7.5

 

2

3

3

4

5

5

8.0

 

 

 

2

2

2

2

8.0

 

 

2

2

2

3

3

K mag

5L1R

5L2R

5L3R

5L4R

5L5R

5L6R

5L7R

K mag

6L1R

6L2R

6L3R

6L4R

6L5R

6L6R

6L7R

2.5

162

 

 

 

 

 

 

2.5

 

 

 

 

 

 

 

3.0

102

154

 

 

 

 

 

3.0

122

 

 

 

 

 

 

3.5

65

97

130

163

 

 

 

3.5

77

116

156

 

 

 

 

4.0

41

61

82

103

123

144

165

4.0

49

74

98

123

148

172

 

4.5

26

39

52

65

78

91

104

4.5

31

46

62

78

93

109

125

5.0

16

24

33

41

49

57

66

5.0

19

29

39

49

59

69

79

5.5

10

15

21

26

31

36

41

5.5

12

18

25

31

37

43

50

6.0

6

10

13

16

20

23

26

6.0

8

12

16

20

23

27

31

6.5

4

6

8

10

12

14

16

6.5

5

7

10

12

15

17

20

7.0

3

4

5

6

8

9

10

7.0

3

5

6

8

9

11

12

7.5

2

2

3

4

5

6

7

7.5

2

3

4

5

6

7

8

8.0

 

2

2

3

3

4

4

8.0

 

2

2

3

4

4

5

K mag

7L1R

7L2R

7L3R

7L4R

7L5R

7L6R

7L7R

K mag

7L1R

7L2R

7L3R

7L4R

7L5R

7L6R

7L7R

3.0

142

 

 

 

 

 

 

6.0

9

14

18

23

27

32

36

3.5

90

136

182

 

 

 

 

6.5

6

9

11

14

17

20

23

4.0

57