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A low-cost ultraviolet-to-infrared absolute quantum efficiency characterization system of detectors
Authors:
Ajay S. Gill,
Mohamed M. Shaaban,
Aaron Tohuvavohu,
Suresh Sivanandam,
Roberto G. Abraham,
Seery Chen,
Maria R. Drout,
Deborah Lokhorst,
Christopher D. Matzner,
Stefan W. Mochnacki,
Calvin B. Netterfield
Abstract:
We present a low-cost ultraviolet to infrared absolute quantum efficiency detector characterization system developed using commercial off-the-shelf components. The key components of the experiment include a light source,a regulated power supply, a monochromator, an integrating sphere, and a calibrated photodiode. We provide a step-by-step procedure to construct the photon and quantum efficiency tr…
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We present a low-cost ultraviolet to infrared absolute quantum efficiency detector characterization system developed using commercial off-the-shelf components. The key components of the experiment include a light source,a regulated power supply, a monochromator, an integrating sphere, and a calibrated photodiode. We provide a step-by-step procedure to construct the photon and quantum efficiency transfer curves of imaging sensors. We present results for the GSENSE 2020 BSI CMOS sensor and the Sony IMX 455 BSI CMOS sensor. As a reference for similar characterizations, we provide a list of parts and associated costs along with images of our setup.
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Submitted 26 July, 2022;
originally announced July 2022.
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Radial Velocity Studies of Close Binary Stars.XIII
Authors:
Slavek M. Rucinski,
Theodor Pribulla,
Stefan W. Mochnacki,
Evgenij Liokumovich,
Wenxian Lu,
Heide DeBond,
Archie de Ridder,
Toomas Karmo,
Matt Rock,
J. R. Thomson,
Waldemar Ogloza,
Krysztof Kaminski,
Piotr Ligeza
Abstract:
Radial-velocity measurements and sine-curve fits to the orbital radial velocity variations are presented for ten close binary systems: EG Cep,V1191 Cyg, V1003 Her, BD+7_3142, V357 Peg, V407 Peg, V1123 Tau, V1128 Tau, HH UMa, and PY Vir. While most of the studied eclipsing systems are contact binaries, EG Cep is a detached or a semi-detached double-lined binary and V1003 Her is a close binary of…
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Radial-velocity measurements and sine-curve fits to the orbital radial velocity variations are presented for ten close binary systems: EG Cep,V1191 Cyg, V1003 Her, BD+7_3142, V357 Peg, V407 Peg, V1123 Tau, V1128 Tau, HH UMa, and PY Vir. While most of the studied eclipsing systems are contact binaries, EG Cep is a detached or a semi-detached double-lined binary and V1003 Her is a close binary of an uncertain type seen at a very low inclination angle. We discovered two previously unknown triple systems, BD+7_3142 and PY Vir, both with late spectral-type (K2V) binaries. Of interest is the low-mass ratio (q = 0.106) close binary V1191 Cyg showing an extremely fast period increase; the system has a very short period for its spectral type and shows a W-type light curve, a feature rather unexpected for such a low mass-ratio system.
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Submitted 12 May, 2008;
originally announced May 2008.
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Radial Velocity Studies of Close Binary Stars. XI
Authors:
Theodor Pribulla,
Slavek M. Rucinski,
Wenxian Lu,
Stefan W. Mochnacki,
George Conidis,
R. M. Blake,
Heide DeBond,
J. R. Thomson,
Wojtek Pych,
Waldemar Ogloza,
Michal Siwak
Abstract:
Radial-velocity measurements and sine-curve fits to the orbital radial velocity variations are presented for ten close binary systems: DU Boo, ET Boo, TX Cnc, V1073 Cyg, HL Dra, AK Her, VW LMi, V566 Oph, TV UMi and AG Vir. By this contribution, the DDO program has reached the point of 100 published radial velocity orbits. The radial velocities have been determined using an improved fitting techn…
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Radial-velocity measurements and sine-curve fits to the orbital radial velocity variations are presented for ten close binary systems: DU Boo, ET Boo, TX Cnc, V1073 Cyg, HL Dra, AK Her, VW LMi, V566 Oph, TV UMi and AG Vir. By this contribution, the DDO program has reached the point of 100 published radial velocity orbits. The radial velocities have been determined using an improved fitting technique which uses rotational profiles to approximate individual peaks in broadening functions.
Three systems, ET Boo, VW LMi and TV UMi, were found to be quadruple while AG Vir appears to be a spectroscopic triple. ET Boo, a member of a close visual binary with $P_{vis} = 113$ years, was previously known to be a multiple system, but we show that the second component is actually a close, non-eclipsing binary. The new observations enabled us to determine the spectroscopic orbits of the companion, non-eclipsing pairs in ET Boo and VW LMi. The particularly interesting case is VW LMi, where the period of the mutual revolution of the two spectroscopic binaries is only 355 days.
While most of the studied eclipsing pairs are contact binaries, ET Boo is composed of two double-lined detached binaries and HL Dra is single-lined detached or semi-detached system. Five systems of this group were observed spectroscopically before: TX Cnc, V1073 Cyg, AK Her (as a single-lined binary), V566 Oph, AG Vir, but our new data are of much higher quality than the previous studies.
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Submitted 15 May, 2006;
originally announced May 2006.
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Radial Velocity Studies of Close Binary Stars.X
Authors:
Slavek M. Rucinski,
Wojtek Pych,
Waldemar Ogloza,
Heide DeBond,
J. R. Thomson,
Stefan W. Mochnacki,
Christopher C. Capobianco,
George Conidis,
P. Rogoziecki
Abstract:
Radial-velocity measurements and sine-curve fits to the orbital velocity variations are presented for the ninth set of ten close binary systems: V395 And, HS Aqr, V449 Aur, FP Boo, SW Lac, KS Peg, IW Per, V592 Per, TU UMi, FO Vir. The first three are very close, possibly detached, early-type binaries and all three require further investigation. Particularly interesting is V395 And whose spectral…
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Radial-velocity measurements and sine-curve fits to the orbital velocity variations are presented for the ninth set of ten close binary systems: V395 And, HS Aqr, V449 Aur, FP Boo, SW Lac, KS Peg, IW Per, V592 Per, TU UMi, FO Vir. The first three are very close, possibly detached, early-type binaries and all three require further investigation. Particularly interesting is V395 And whose spectral type is as early as B7/8 for a 0.685 day orbit binary. KS Peg and IW Per are single-line binaries, with the former probably hosting a very low mass star. We have detected a low-mass secondary in an important semi-detached system FO Vir at q=0.125+/-0.005. The contact binary FP Boo is also a very small mass-ratio system, q=0.106+/-0.005. The other contact binaries in this group are V592 Per, TU UMi and the well known SW Lac. V592 Per and TU UMi have bright tertiary companions; for these binaries, and for V395 And, we used a novel technique of the broadening functions arranged into a 2-dimensional image in phase. The case of TU UMi turned out intractable even using this approach and we have not been able to derive a firm radial velocity orbit for this binary. Three systems of this group were observed spectroscopically before: HS Aqr, SW Lac, KS Peg.
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Submitted 21 April, 2005; v1 submitted 2 March, 2005;
originally announced March 2005.
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Distance of the Hypernova SN 2002ap via the Expanding Photosphere Method
Authors:
J. Vinko,
R. M. Blake,
K. Sarneczky,
B. Csak,
G. Furesz,
Sz. Csizmadia,
L. L. Kiss,
Gy. M. Szabo,
R. Szabo,
H. DeBond,
M. M. de Robertis,
J. R. Thomson,
S. W. Mochnacki
Abstract:
New optical photometric and spectroscopic data of the bright hypernova SN 2002ap are presented. The obtained BVRI light curves as well as the optical spectra agree well with other published data series. The distance has been inferred by applying the Expanding Photosphere Method for the data around maximum. The derived 6.7 Mpc is in good agreement with recent photometric distances of M74. However…
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New optical photometric and spectroscopic data of the bright hypernova SN 2002ap are presented. The obtained BVRI light curves as well as the optical spectra agree well with other published data series. The distance has been inferred by applying the Expanding Photosphere Method for the data around maximum. The derived 6.7 Mpc is in good agreement with recent photometric distances of M74. However, the total (random plus systematic) uncertainty of the EPM-distance is at least 4.5 Mpc (about 70 %). The physical parameters of the SN have been determined via simplified analytic models of the light and velocity curves. It is confirmed that SN 2002ap was a less energetic hypernova, the kinetic energy was 4 - 8 10^51 erg, and the reddening-free absolute bolometric magnitude reached -16.63 mag (corresponding to L_bol = 3.47 10^8 L_solar), about 2 magnitude less than the prototype hypernova SN 1998bw.
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Submitted 31 August, 2004;
originally announced August 2004.
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Radial Velocity Studies of Close Binary Stars.VIII
Authors:
S. M. Rucinski,
C. C. Capobianco,
W. Lu,
H. DeBond,
J. R. Thomson,
S. W. Mochnacki,
R. M. Blake,
W. Ogloza,
G. Stachowski,
P. Rogoziecki
Abstract:
Radial-velocity measurements and sine-curve fits to the orbital velocity variations are presented for the seventh set of ten close binary systems: V410 Aur, V523 Cas, QW Gem, V921 Her, V2357 Oph, V1130 Tau, HN UMa, HX UMa, HD 93917, NSV 223. All systems, but three (V523 Cas, HD 93917, NSV 223), were discovered photometrically by the Hipparcos mission. All systems are double-lined (SB2) binaries…
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Radial-velocity measurements and sine-curve fits to the orbital velocity variations are presented for the seventh set of ten close binary systems: V410 Aur, V523 Cas, QW Gem, V921 Her, V2357 Oph, V1130 Tau, HN UMa, HX UMa, HD 93917, NSV 223. All systems, but three (V523 Cas, HD 93917, NSV 223), were discovered photometrically by the Hipparcos mission. All systems are double-lined (SB2) binaries and all, but the detached, very close system V1130 Tau, are contact binaries. The broadening-function permitted improvement of the orbital elements for V523 Cas, which was the only system observed before for radial velocity variations. Spectroscopic/visual companions were detected for V410 Aur and HX UMa.
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Submitted 19 February, 2003;
originally announced February 2003.
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A Spectroscopic Survey of a Sample of Active M Dwarfs
Authors:
Stefan W. Mochnacki,
Michael D. Gladders,
James R. Thomson,
Wenxian Lu,
Paula Ehlers,
Metin Guler,
Asif Hussain,
Quincy Kameda,
Karen King,
Patricia Mitchell,
Jason Rowe,
Peter Schindler,
Heather Scott
Abstract:
A moderate resolution spectroscopic survey of Fleming's sample of 54 X-ray selected M dwarfs with photometric distances less than 25 pc is presented. Radial and rotation velocities have been measured by fits to the H-alpha profiles. Radial velocities have been measured by cross correlation. Artificial broadening of an observed spectrum has produced a relationship between H-alpha FWHM and rotatio…
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A moderate resolution spectroscopic survey of Fleming's sample of 54 X-ray selected M dwarfs with photometric distances less than 25 pc is presented. Radial and rotation velocities have been measured by fits to the H-alpha profiles. Radial velocities have been measured by cross correlation. Artificial broadening of an observed spectrum has produced a relationship between H-alpha FWHM and rotation speed, which we use to infer rotation speeds for the entire sample by measurement of the H-alpha emission line. We find 3 ultra-fast rotators (UFRs, vsini > 100km/s), and 8 stars with 30 < vsini < 100 km/s. The UFRs have variable emission. Cross-correlation velocities measured for ultra-fast rotators (UFRs) are shown to depend on rotation speed and the filtering used. The radial velocity dispersion of the sample is 17 km/s. A new double emission line spectroscopic binary with a period of 3.55 days has been discovered, and another known one is in the sample. Three other objects are suspected spectroscopic binaries, and at least six are visual doubles. The only star in the sample observed to have significant lithium is a known TW Hya Association member, TWA 8A. These results show that there are a number of young (< 10^8 yr) and very young (< 10^7 yr) low mass stars in the immediate solar neighbourhood. The H-alpha activity strength does not depend on rotation speed. Our fast rotators are less luminous than similarly fast rotators in the Pleiades. They are either younger than the Pleiades, or gained angular momentum in a different way.
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Submitted 18 July, 2002;
originally announced July 2002.
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Radial Velocity Studies of Close Binary Stars.VI
Authors:
S. M. Rucinski,
W. Lu,
C. Capobianco,
S. W. Mochnacki,
R. M. Blake,
J. R. Thomson,
W. Ogloza,
G. Stachowski
Abstract:
Radial-velocity measurements and sine-curve fits to the orbital velocity variations are presented for the sixth set of ten close binary systems: SV Cam, EE Cet, KR Com, V410 Cyg, GM Dra, V972 Her, ET Leo, FS Leo, V2388 Oph, II UMa. All systems except FS Leo are double-lined spectroscopic binaries. The type of FS Leo is unknown while SV Cam is a close, detached binary; all remaining systems are c…
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Radial-velocity measurements and sine-curve fits to the orbital velocity variations are presented for the sixth set of ten close binary systems: SV Cam, EE Cet, KR Com, V410 Cyg, GM Dra, V972 Her, ET Leo, FS Leo, V2388 Oph, II UMa. All systems except FS Leo are double-lined spectroscopic binaries. The type of FS Leo is unknown while SV Cam is a close, detached binary; all remaining systems are contact binaries. Eight binaries (all except SV Cam and V401 Cyg) are the recent photometric discoveries of the Hipparcos satellite project. Five systems, EE Cet, KR Com, V401 Cyg, V2388 Oph, II UMa, are members of visual/spectroscopic triple systems. We were able to observe the close binary system EE Cet separately of its companion, but in the remaining four systems we could separate the spectral components only through the use of the broadening-function approach. Several of the studied systems are prime candidates for combined light and radial-velocity synthesis solutions.
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Submitted 29 May, 2002; v1 submitted 14 January, 2002;
originally announced January 2002.
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Radial Velocity Studies of Close Binary Stars.V
Authors:
S. M. Rucinski,
W. Lu,
S. W. Mochnacki,
W. Ogloza G. Stachowski
Abstract:
Radial-velocity measurements and sine-curve fits to the orbital velocity variations are presented for the fifth set of ten close binary systems: V376 And, EL Aqr, EF Boo, DN Cam, FN Cam, V776 Cas, SX Crv, V351 Peg, EQ Tau, KZ Vir. All systems are double-lined spectroscopic contact binaries (KZ Vir may be a low inclination, close, non-contact binary), with seven (all except EL Aqr, SX Crv and EQ…
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Radial-velocity measurements and sine-curve fits to the orbital velocity variations are presented for the fifth set of ten close binary systems: V376 And, EL Aqr, EF Boo, DN Cam, FN Cam, V776 Cas, SX Crv, V351 Peg, EQ Tau, KZ Vir. All systems are double-lined spectroscopic contact binaries (KZ Vir may be a low inclination, close, non-contact binary), with seven (all except EL Aqr, SX Crv and EQ Tau) being the recent photometric discoveries of the Hipparcos satellite project. The most interesting object is SX Crv, a contact system with an unprecedently low mass ratio, q=0.066+/-0.003, whose existence challenges the current theory of tidal stability of contact systems. Several of the studied systems are prime candidates for combined light and radial-velocity synthesis solutions.
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Submitted 8 June, 2001;
originally announced June 2001.
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The Peculiar Type Ia Supernova 1999by: Spectroscopy at Early Epochs
Authors:
J. Vinko,
L. L. Kiss,
B. Csak,
G. Furesz,
R. Szabo,
J. R. Thomson,
S. W. Mochnacki
Abstract:
We present medium resolution (lambda/Delta lambda = 2500) optical spectroscopy of SN 1999by in NGC 2841 made around its light maximum. The depth ratio of the two Si II features at 5800 AA and 6150 AA being R(SiII) approx. 0.63 at maximum indicates that this SN belongs to the peculiar, sub-luminous SNe Ia. Radial velocities inferred from the minimum of the 6150 AA trough reveal a steeper decline…
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We present medium resolution (lambda/Delta lambda = 2500) optical spectroscopy of SN 1999by in NGC 2841 made around its light maximum. The depth ratio of the two Si II features at 5800 AA and 6150 AA being R(SiII) approx. 0.63 at maximum indicates that this SN belongs to the peculiar, sub-luminous SNe Ia. Radial velocities inferred from the minimum of the 6150 AA trough reveal a steeper decline of the velocity curve than expected for ``normal'' SNe Ia, consistent with the behavior of published VRI light curves. A revised absolute magnitude of SN 1999by and distance to its host galaxy NGC 2841 is estimated based on the Multi-Color Light Curve Shape (MLCS) method, resulting in M_V(max)=-18.06+/- 0.1 mag and d = 17.1+/-1.2 Mpc, respectively. An approximative linear dependence of the luminosity parameter Delta on R(SiII) is presented.
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Submitted 2 March, 2001;
originally announced March 2001.
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Radial Velocity Studies of Close Binary Stars.III
Authors:
Slavek M. Rucinski,
Wenxian Lu,
Stefan W. Mochnacki
Abstract:
Radial velocity measurements and simple sine-curve fits to the orbital velocity variations are presented for the third set of ten contact binary systems: CN And, HV Aqr, AO Cam, YY CrB, FU Dra, RZ Dra, UX Eri, RT LMi, V753 Mon, OU Ser. All systems but two are contact, double-line spectroscopic binaries with four of them (YY CrB, FU Dra, V753 Mon, OU Ser) being the recent discoveries of the Hippa…
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Radial velocity measurements and simple sine-curve fits to the orbital velocity variations are presented for the third set of ten contact binary systems: CN And, HV Aqr, AO Cam, YY CrB, FU Dra, RZ Dra, UX Eri, RT LMi, V753 Mon, OU Ser. All systems but two are contact, double-line spectroscopic binaries with four of them (YY CrB, FU Dra, V753 Mon, OU Ser) being the recent discoveries of the Hipparcos satellite project. The most interesting object is V753 Mon with the mass-ratio closest to unity among all contact systems (q = 0.970 pm 0.003) and large total mass ((M1+M2)sin^3i = 2.93 pm 0.06). Several of the studied systems are prime candidates for combined light and radial-velocity synthesis solutions.
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Submitted 8 February, 2000;
originally announced February 2000.
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The DDO IVC Distance Project
Authors:
Michael D. Gladders,
Tracy E. Clarke,
Christopher R. Burns,
Allen Attard,
Michael P. Casey,
Devon Hamilton,
Gabriela Mallen-Ornelas,
Jennifer L. Karr,
Sara M. Poirier,
Marcin Sawicki,
Felipe Barrientos,
Wayne Barkhouse,
Mark Brodwin,
Jason Clark,
Rosemary McNaughton,
Marcelo Ruetalo-Pacheco,
Stefan W. Mochnacki
Abstract:
We present the first set of distance limits from the David Dunlap Observatory Intermediate Velocity Cloud (DDO IVC) distance project. Such distance measures are crucial to understanding the origins and dynamics of IVCs, as the distances set most of the basic physical parameters for the clouds. Currently there are very few IVCs with reliably known distances. This paper describes in some detail th…
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We present the first set of distance limits from the David Dunlap Observatory Intermediate Velocity Cloud (DDO IVC) distance project. Such distance measures are crucial to understanding the origins and dynamics of IVCs, as the distances set most of the basic physical parameters for the clouds. Currently there are very few IVCs with reliably known distances. This paper describes in some detail the basic techniques used to measure distances, with particular emphasis on the the analysis of interstellar absorption line data, which forms the basis of our distance determinations. As an example, we provide a detailed description of our distance determination for the Draco Cloud. Preliminary distance limits for a total of eleven clouds are provided.
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Submitted 18 November, 1998;
originally announced November 1998.
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The Distance to the Draco Cloud
Authors:
Michael D. Gladders,
T. E. Clarke,
Christopher R. Burns,
A. Attard,
M. P. Casey,
Devon Hamilton,
Gabriela Mallén-Ornelas,
J. L. Karr,
Sara M. Poirier,
Marcin Sawicki,
L. Felipe Barrientos,
Stefan W. Mochnacki
Abstract:
The understanding of the nature of intermediate and high velocity gas in the Milky Way is hampered by a paucity of distance estimates to individual clouds. A project has been started at the David Dunlap Observatory to address this lack of distance measures by observing early-type stars along the line of sight towards these clouds and searching for sodium doublet absorption at the clouds' systemi…
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The understanding of the nature of intermediate and high velocity gas in the Milky Way is hampered by a paucity of distance estimates to individual clouds. A project has been started at the David Dunlap Observatory to address this lack of distance measures by observing early-type stars along the line of sight towards these clouds and searching for sodium doublet absorption at the clouds' systemic velocities. Distances to foreground stars (no absorption) and background stars (with absorption) are estimated from spectroscopic parallax, and thus the distance to the bracketed cloud is estimated. In this Letter, we present the first result from this ongoing project, a measurement of the distance to the Draco Cloud, which is the most studied of the intermediate velocity clouds. The result presented here is the first distance bracket which tightly constrains the position of the Draco Cloud. We briefly describe our target selection and observing methodology, and then demonstrate absorption at the velocity of the Draco Cloud for one star (TYC~4194~2188), and a lack of absorption for several other stars. We derive a distance bracket to the Draco Cloud of 463$^{+192}_{-136}$ to 618$^{+243}_{-174}$~pc.
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Submitted 14 September, 1998;
originally announced September 1998.