Impact of crosshatch patterns in H2RGs on high-precision radial velocity measurements: exploration of measurement and mitigation paths with the Habitable-Zone Planet Finder

AbstractWe have a plan to conduct a Doppler planet search for low-mass planets around nearby middle-to-late M dwarfs using IRD. IRD is the near-infrared high-precision radial velocity instrument for the Subaru 8.2-m telescope. We expect to achieve the accuracy of the radial velocity measurements of 1 m/s using IRD with a frequency comb as a wavelengh calibrator. Thus, we would detect super-Earths in habitable zone and low-mass rocky planets in close-in orbits around late-M dwarfs. In this survey, we aim to understand and discuss statistical properties of low-mass planets around low-mass M dwarfs compared with those derived from theoretical simulations.

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Stellar noise and planet detection. I. Oscillations, granulation and sun-like spots

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311021089 ◽

2010 ◽

Vol 6 (S276) ◽

pp. 527-529

Author(s):

Xavier Dumusque ◽

Nuno C. Santos ◽

Stéphane Udry ◽

Cristophe Lovis ◽

Xavier Bonfils

Keyword(s):

Radial Velocity ◽

Time Scales ◽

High Precision ◽

Habitable Zone ◽

Planet Detection ◽

Solar Type ◽

Physical Phenomena ◽

Instrumental Precision ◽

Observational Strategy ◽

Different Time Scales

AbstractSpectrographs like HARPS can now reach a sub-ms−1 precision in radial-velocity (RV) (Pepe & Lovis 2008). At this level of accuracy, we start to be confronted with stellar noise produced by 3 different physical phenomena: oscillations, granulation phenomena (granulation, meso- and super-granulation) and activity. On solar type stars, these 3 types of perturbation can induce ms−1 RV variation, but on different time scales: 3 to 15 minutes for oscillations, 15 minutes to 1.5 days for granulation phenomena and 10 to 50 days for activity. The high precision observational strategy used on HARPS, 1 measure per night of 15 minutes, on 10 consecutive days each month, is optimized, due to a long exposure time, to average out the noise coming from oscillations (Dumusque et al. 2011a) but not to reduce the noise coming from granulation and activity (Dumusque et al. 2011a and Dumusque et al. 2011b). The smallest planets found with this strategy (Mayor et al. 2009) seems to be at the limit of the actual observational strategy and not at the limit of the instrumental precision. To be able to find Earth mass planets in the habitable zone of solar-type stars (200 days for a K0 dwarf), new observational strategies, averaging out simultaneously all type of stellar noise, are required.

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Densified Pupil Spectrograph as High-precision Radial Velocimetry: From Direct Measurement of the Universe’s Expansion History to Characterization of Nearby Habitable Planet Candidates

The Astronomical Journal ◽

10.3847/1538-3881/ac397b ◽

2022 ◽

Vol 163 (2) ◽

pp. 63

Author(s):

Taro Matsuo ◽

Thomas P. Greene ◽

Mahdi Qezlou ◽

Simeon Bird ◽

Kiyotomo Ichiki ◽

...

Keyword(s):

Radial Velocity ◽

Direct Measurement ◽

High Precision ◽

Resolving Power ◽

Line Of Sight ◽

High Dispersion ◽

Velocity Measurements ◽

Habitable Planet ◽

Airy Disk

Abstract The direct measurement of the universe’s expansion history and the search for terrestrial planets in habitable zones around solar-type stars require extremely high-precision radial-velocity measures over a decade. This study proposes an approach for enabling high-precision radial-velocity measurements from space. The concept presents a combination of a high-dispersion densified pupil spectrograph and a novel line-of-sight monitor for telescopes. The precision of the radial-velocity measurements is determined by combining the spectrophotometric accuracy and the quality of the absorption lines in the recorded spectrum. Therefore, a highly dispersive densified pupil spectrograph proposed to perform stable spectroscopy can be utilized for high-precision radial-velocity measures. A concept involving the telescope’s line-of-sight monitor is developed to minimize the change of the telescope’s line of sight over a decade. This monitor allows the precise measurement of long-term telescope drift without any significant impact on the Airy disk when the densified pupil spectra are recorded. We analytically derive the uncertainty of the radial-velocity measurements, which is caused by the residual offset of the lines of sight at two epochs. We find that the error could be reduced down to approximately 1 cm s−1, and the precision will be limited by another factor (e.g., wavelength calibration uncertainty). A combination of the high-precision spectrophotometry and the high spectral resolving power could open a new path toward the characterization of nearby non-transiting habitable planet candidates orbiting late-type stars. We present two simple and compact highly dispersed densified pupil spectrograph designs for cosmology and exoplanet sciences.

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Searching for Planetary Companions to Ultracool Dwarfs: Planet Hunting in the Near Infrared

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308026616 ◽

2008 ◽

Vol 4 (S253) ◽

pp. 346-349

Author(s):

Cullen H. Blake ◽

David Charbonneau ◽

David W. Latham

Keyword(s):

Radial Velocity ◽

Near Infrared ◽

Extrasolar Planets ◽

Terrestrial Planets ◽

Habitable Zone ◽

Velocity Measurements ◽

Ultracool Dwarfs

AbstractOwing to their small masses and radii, Ultracool Dwarfs (UCDs; late-M, L, and T dwarfs) may be excellent targets for planet searches and may afford astronomers the opportunity to detect terrestrial planets in the habitable zone. The precise measurements necessary to detect extrasolar planets orbiting UCDs represent a major challenge. We describe two efforts to obtain precise measurements of UCDs in the Near Infrared (NIR). The first involves the robotic NIR observatory PAIRITEL and efforts to obtain photometric precision sufficient for the detection of terrestrial planets transiting UCDs. The second effort involves precise radial velocity measurements of UCDs in the NIR and a survey undertaken with the NIRSPEC spectrograph on Keck.

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Proxima’s orbit around α Centauri

Astronomy and Astrophysics ◽

10.1051/0004-6361/201629930 ◽

2017 ◽

Vol 598 ◽

pp. L7 ◽

Cited By ~ 53

Author(s):

P. Kervella ◽

F. Thévenin ◽

C. Lovis

Keyword(s):

Radial Velocity ◽

High Precision ◽

Orbital Period ◽

Triple System ◽

Orbital Motion ◽

The Sun ◽

Proper Motions ◽

Velocity Measurements ◽

Degree Of Confidence ◽

High Degree

Proxima and α Centauri AB have almost identical distances and proper motions with respect to the Sun. Although the probability of such similar parameters is, in principle, very low, the question as to whether they actually form a single gravitationally bound triple system has been open since the discovery of Proxima one century ago. Owing to HARPS high-precision absolute radial velocity measurements and the recent revision of the parameters of the α Cen pair, we show that Proxima and α Cen are gravitationally bound with a high degree of confidence. The orbital period of Proxima is ≈ 550 000 yr. With an eccentricity of 0.50+0.08-0.09, Proxima comes within 4.3+1.1-0.9 kau of α Cen at periastron, and is currently close to apastron (13.0+0.3-0.1 kau). This orbital motion may have influenced the formation or evolution of the recently discovered planet orbiting Proxima, as well as circumbinary planet formation around α Cen.

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Charge Transfer Inefficiency effect for high-precision radial velocity measurements

EAS Publications Series ◽

10.1051/eas/0937031 ◽

2009 ◽

Vol 37 ◽

pp. 247-253 ◽

Cited By ~ 29

Author(s):

F. Bouchy ◽

J. Isambert ◽

C. Lovis ◽

I. Boisse ◽

P. Figueira ◽

...

Keyword(s):

Charge Transfer ◽

Radial Velocity ◽

High Precision ◽

Velocity Measurements

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Towards a fully automated eclipsing binary solver for Gaia

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308026768 ◽

2008 ◽

Vol 4 (S253) ◽

pp. 402-403

Author(s):

Brandon Tingley ◽

Gilles Sadowski ◽

Christos Siopis

Keyword(s):

Radial Velocity ◽

High Precision ◽

Eclipsing Binaries ◽

Physical Parameters ◽

Graphical Interface ◽

Velocity Measurements ◽

New Approach ◽

Eclipsing Binary ◽

Photometric Observations

AbstractGaia, an ESA cornerstone mission, will obtain of the order of 100 high-precision photometric observations and lower precision radial velocity measurements over five years for around a billion stars – several hundred thousand of which will be eclipsing binaries. In order to extract the characteristics of these systems, a fully automated code must be available. During the process of this development, two tools that may be of use to the transit community have emerged: a very fast, simple, detached eclipsing binary simulator/solver based on a new approach and an interacting eclipsing binary simulator with most of the features of the Wilson-Devinney and Nightfall codes, but fully documented and written in easy-to-follow and highly portable Java. Currently undergoing development and testing, this code includes an intuitive graphical interface and an optimizer for the estimation of the physical parameters of the system.

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Some comments on the design of échelle spectrographs using R2 or R4 gratings for precise radial-velocity measurements

International Astronomical Union Colloquium ◽

10.1017/s0252921100048302 ◽

1999 ◽

Vol 170 ◽

pp. 29-35

Author(s):

John Hearnshaw ◽

Norman Rumsey ◽

Garry Nankivell

Keyword(s):

Radial Velocity ◽

High Precision ◽

Velocity Measurements ◽

Single Exposure ◽

Echelle Spectrograph ◽

Moving Parts

AbstractA new fiber-fed échelle spectrograph (Hercules) is being designed for the 1-m telescope at Mt John University Observatory. The goals are to have a wavelength capability of 380 to 880 nm, covered in a single exposure on a 50-mm square CCD, to have a choice of resolving powers of 35000 or 70000 and to have no moving parts. High precision radialvelocity observations are a major but not the only goal. Designs with both R2 (blaze angle 63.4 deg) and R4 (blaze angle 76 deg) échelle gratings are being considered, in either case with a dimension of 408 mm perpendicular to the grooves.

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High Precision Photometry from EulerCam and TRAPPIST: The Case of WASP-42, WASP-49 and WASP-50

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313012660 ◽

2012 ◽

Vol 8 (S293) ◽

pp. 119-121

Author(s):

Monika Lendl ◽

Michaël Gillon ◽

Didier Queloz

Keyword(s):

Radial Velocity ◽

High Precision ◽

Extrasolar Planets ◽

High Accuracy ◽

Velocity Measurements ◽

Very High

AbstractTransiting extrasolar planets provide unmatched insights into the structure and composition of close-in planets. When a planet transits its host star, its radius is known, which together with radial velocity measurements, allows accessing the planetary density. We present results obtained using the Euler and TRAPPIST telescopes that aim at reaching very high accuracy on the parameters derived from transit lightcurves. Here, we show the case of the recently discovered WASP-42b and WASP-49b and new observations of WASP-50b.

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Habitable Zone Super-Earths with Non-Stabilised Spectrographs

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313012556 ◽

2012 ◽

Vol 8 (S293) ◽

pp. 68-70

Author(s):

Duncan J. Wright ◽

Christopher G. Tinney ◽

Robert A. Wittenmyer

Keyword(s):

High Resolution ◽

Radial Velocity ◽

High Precision ◽

Calibration Method ◽

Habitable Zone ◽

Absorption Cell ◽

M Dwarfs ◽

Wavelength Calibration ◽

Atmospheric Changes ◽

Rocky Planets

AbstractDetecting the small velocity amplitudes (≤ 10 m/s) produced by habitable zone rocky planets around M Dwarfs requires radial velocity precisions of a few m s−1. However, an iodine absorption cell, commonly used as a high precision wavelength reference on non-stabilised spectrographs, is not efficient for very red and faint objects like M Dwarfs. Instead, arc lamps have to be used. With the exception of the ultra-stabilised HARPS spectrograph, achieving ~m s−1 calibration with arc lamps has not been possible because typical spectrographs experience drifts of several hundred m s−1 due to local atmospheric changes in pressure and temperature. We outline and present results from an innovative differential wavelength calibration method that enables ~m s−1 precision from non-stabilised, high-resolution spectrographs. This technique allows the detection of rocky planets with radial velocity amplitudes of a few m s−1.

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