adsabs/AstroCLIMB huggingface dataset:
Paper: Planet Hunters TESS. V. A Planetary System Around a Binary Star, Including a Mini-Neptune in the Habitable Zone
Authors: Nora L. Eisner, Samuel K. Grunblatt, Oscar Barragán, Thea H. Faridani, Chris Lintott, Suzanne Aigrain, Cole Johnston, Ian R. Mason, Keivan G. Stassun, Megan Bedell, Andrew W. Boyle, David R. Ciardi, Catherine A. Clark, Guillaume Hebrard, David W. Hogg, Steve B. Howell, Baptiste Klein, Joe Llama, Joshua N. Winn, Lily L. Zhao, Joseph M. Akana Murphy, Corey Beard, Casey L. Brinkman, Ashley Chontos, Pia Cortes-Zuleta, Xavier Delfosse, Steven Giacalone, Emily A. Gilbert, Neda Heidari, Rae Holcomb, Jon M. Jenkins, Flavien Kiefer, Jack Lubin, Eder Martioli, Alex S. Polanski, Nicholas Saunders, Sara Seager, Avi Shporer, Dakotah Tyler, Judah Van Zandt, Safaa Alhassan, Daval J. Amratlal, Lais I. Antonel, Simon L. S. Bentzen, Milton K. D Bosch, David Bundy, Itayi Chitsiga, Jérôme F. Delaunay, Xavier Doisy, Richard Ferstenou, Mark Fynø, James M. Geary, Gerry Haynaly, Pete Hermes, Marc Huten, Sam Lee, Paul Metcalfe, Garry J. Pennell, Joanna Puszkarska, Thomas Schäfer, Lisa Stiller, Christopher Tanner, Allan Tarr, Andrew Wilkinson
Figure caption: The three transits of TOI 4633 c. Nominal TESS observations are shown in light gray while solid circles represent 60 minutes binned data.
Paper: Planet Hunters TESS. V. A Planetary System Around a Binary Star, Including a Mini-Neptune in the Habitable Zone
Authors: Nora L. Eisner, Samuel K. Grunblatt, Oscar Barragán, Thea H. Faridani, Chris Lintott, Suzanne Aigrain, Cole Johnston, Ian R. Mason, Keivan G. Stassun, Megan Bedell, Andrew W. Boyle, David R. Ciardi, Catherine A. Clark, Guillaume Hebrard, David W. Hogg, Steve B. Howell, Baptiste Klein, Joe Llama, Joshua N. Winn, Lily L. Zhao, Joseph M. Akana Murphy, Corey Beard, Casey L. Brinkman, Ashley Chontos, Pia Cortes-Zuleta, Xavier Delfosse, Steven Giacalone, Emily A. Gilbert, Neda Heidari, Rae Holcomb, Jon M. Jenkins, Flavien Kiefer, Jack Lubin, Eder Martioli, Alex S. Polanski, Nicholas Saunders, Sara Seager, Avi Shporer, Dakotah Tyler, Judah Van Zandt, Safaa Alhassan, Daval J. Amratlal, Lais I. Antonel, Simon L. S. Bentzen, Milton K. D Bosch, David Bundy, Itayi Chitsiga, Jérôme F. Delaunay, Xavier Doisy, Richard Ferstenou, Mark Fynø, James M. Geary, Gerry Haynaly, Pete Hermes, Marc Huten, Sam Lee, Paul Metcalfe, Garry J. Pennell, Joanna Puszkarska, Thomas Schäfer, Lisa Stiller, Christopher Tanner, Allan Tarr, Andrew Wilkinson
Figure caption: Corner plot of the posteriors of the ORBITIZE! results.
Paper: The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study
Authors: T. J. Davidge
Figure caption: (Top panel) Information extracted from the characteristic curve calibration region on the 1963 plate. Mean signal levels in four 10.5 mm wide strips, labeled C1 through C4, that cut through the calibration area are shown. The calibration region consists of five steps with signal levels that vary along the dispersion direction, and the boundaries between the steps in the region examined here are indicated by the vertical dotted lines; scattered light and the Eberhard effect blur the step edges and tilt the signal within each step. The signal in steps 4 and 5 is more or less flat in C1 and C2, suggesting that the signal is close to saturation and samples the upper part of the characteristic curve. Flattening at the bright end is much less noticeable in C3 and C4, which sample lower signal levels. A linear relation through the midpoints of each step with a slope 0.3 dex per step will be present if the signal is linear, and the dashed red lines are relations with a slope 0.3 dex/step that was fit to the central light levels in steps 1–4; this relation was not fit to C1 because of the obvious nonlinearity at the bright end of this curve. The linear relations match the curves at signal levels log(DU) ⪅ 1.85, indicated by the dashed green line, which we identify as the upper limit for a linear response. The comparisons in the top panel also indicate that the signal is linear down to light levels of at least log(DU) ∼ 0.5. (Bottom panel) The partially processed mean 1963 spectrum. The dashed green lines mark the interval over which the signal is expected to be linear, based on the comparisons in the top panel. The line at log(DU) = 0.5 is an upper limit. Note that Hγ and much of the continuum fall within the linear interval. Moderately weak absorption features in the high S/N part of the spectrum also fall within the linear boundaries, although they are close to the upper limit for linearity. The applicability of the linear response region is tested through comparisons with a CCD spectrum in Section 6.4.
Paper: The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study
Authors: T. J. Davidge
Figure caption: (Top panel) Spectra of Vega recorded in 1925 and digitized at densities of 300, 1200, and 2400 dpi with the Epson V800 scanner. The vertical green lines mark the approximate limits of Hγ, and the location of Mg II 4481 is also marked. There is a clear difference in resolution between the spectra digitized at 300 and 1200 dpi. However, the differences between the spectra scanned at 1200 and 2400 dpi are more subtle, with weak features, such as Mg II 4481, appearing to be slightly better defined in the 2400 dpi spectrum. (Bottom panel) The differences between the 2400 dpi and 1200 dpi spectra, where Δ is the difference in the sense 2400 dpi–1200 dpi. There is a high-frequency component with a ∼ ±0.05% dispersion that is superimposed on a lower frequency modulation with a ±1% amplitude. The former is likely due to noise, while the latter has a peak-to-peak distance that is roughly twice the width of Hγ. There is a ∼0.5% difference between the two spectra near Hγ, in the sense that the central regions of Hγ may be slightly sharper (but not deeper) in the 2400 dpi spectrum. The red line marks the approximate wavelength limits of this peak. As for Mg II 4481, this feature is clearly deeper in the 2400 dpi spectrum. This comparison suggests the use of a scan density of at least 1200 dpi when using the V800 scanner, with a possible preference for 2400 dpi.
Paper: The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study
Authors: T. J. Davidge
Figure caption: Partially processed spectra digitized with the Epson 12000XL scanner at 2400 dpi. The vertical scale shows uncalibrated digital units, while the horizontal axis shows pixels in the scanned image, with wavelength decreasing toward the right. Pixels span 9.5 μm on a plate at this scanning density. The 1949 and 1963 spectra are the means of the spectra that were recorded on each plate. Epoch-to-epoch differences in wavelength coverage, wavelength response, wavelength resolution, and S/N are clearly evident. The 1963 spectrum has the highest wavelength resolution and S/N, and numerous metallic absorption features are clearly seen in that spectrum. The wavelength intervals in the 1963 spectrum that are compared with a CCD spectrum in Figures 11 and 12 are indicated.
Paper: The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study
Authors: T. J. Davidge
Figure caption: (Top panel) Normalized spectra of Vega from the 1949 plate. The Balmer lines in the two spectra differ in two ways. First, the lines in the 1949b spectrum are slightly deeper than in the 1949b spectrum. Second, the Balmer lines in the 1949c spectra are slightly narrower than in the 1949b spectrum, although this likely is due to the difference in line depths. (Bottom panel) The difference between the normalized spectra, in the sense 1949b–1949c. The depths of the Balmer lines in the two spectra differ at the 15%–20% level. The differences near Hβ and Hγ are comparable, even though the former is observed at a wavelength with lower overall throughput than the latter. This comparison demonstrates that one might expect differences in line properties among spectra in the 1.8 m collection that were recorded on the same plate and close together in time. These differences also demonstrate the magnitude of uncertainties that might be expected when making comparisons with spectra recorded with more modern techniques, as is done in Section 6.4.
Paper: The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study
Authors: T. J. Davidge
Figure caption: Wavelength resolution along the slit in 1.8 m telescope Cassegrain spectra of Vega. The right-hand image shows a section of the scanned 1925 Vega spectrum centered on Hγ; the light is dispersed along the vertical axis, while the horizontal axis runs along the slit. Spectra at three locations along the slit are shown to the left, and the change in spectral resolution with location along the slit can be seen. This demonstrates the need to capture the full spectrum in two dimensions when scanning a 1.8 m plate in order to identify an optimum extraction region.
Paper: The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study
Authors: T. J. Davidge
Figure caption: Comparison of a CCD spectrum of Vega taken with the DAO 1.2 m telescope with the mean spectrum extracted from the 1963 photographic plate. The two spectra have similar (but not identical) wavelength resolutions, and the difference in line profiles is attributed in part to the illumination profiles of the spectra (see text).
Paper: The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study
Authors: T. J. Davidge
Figure caption: (Top panel) Spectra of Vega recorded in 1963 and digitized at 2400 and 3600 dpi with the Epson 12000XL scanner. There is substantially more jitter in the 3600 dpi Hγ profile than in the 2400 dpi profile, and this is likely due to scanning at too high a density. This jitter is clearly seen near the core of Hγ in the 3600 dpi spectrum. (Bottom panel) The difference between the two spectra. The difference near Hγ is tilted, suggesting that the 2400 and 3600 dpi spectra have slightly different behavior in the short wavelength shoulder of this line. Based on the comparisons shown in this figure and Figure 5, 2400 dpi is adopted as the default scanning density.
Paper: The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study
Authors: T. J. Davidge
Figure caption: (Top panel) Spectra of Vega recorded in 1925 and digitized at 2400 dpi with the Epson 12000XL and V800 scanners. (Lower panel) The difference between these spectra (Δ), in the sense V800–12000XL. Hγ is narrower and ∼20% deeper in the 12000XL spectrum when compared with the V800 spectrum. This is due to differences in the scanner MTFs, in the sense that the 12000XL scanner has superior angular resolution when scanning at 2400 dpi. The 12000XL is thus preferred for the scanning of spectra.
Paper: The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study
Authors: T. J. Davidge
Figure caption: Processed spectra. The 1949 and 1963 spectra are the means of the multiple spectra recorded on each plate. The spectra have different wavelength resolutions and response characteristics (e.g., Figure 4). Despite having similar wavelength coverage and wavelength dispersion, the depth of Hγ in the 1925 and 1937 spectra clearly differs, and this may be due to the latter having been recorded during twilight. Numerous absorption features are apparent between 4400 and 4600 Å in the 1949 and 1963 spectra, and the detection of these is likely due to the higher wavelength resolution of those spectra.
Paper: High-contrast, High-angular-resolution Optical Speckle Imaging: Uncovering Hidden Stellar Companions
Authors: Steve B. Howell, Arturo O. Martinez, Douglas A. Hope, David R. Ciardi, Stuart M. Jefferies, Fabien R. Baron, Michael B. Lund
Figure caption: This figure demonstrates the performance of our MFBD algorithm vs. that of the standard speckle interferometric (SI) reconstructions. Each example reconstructed image uses the same 60 ms speckle data acquired with ‘Alopeke at the Gemini North 8 m telescope. The left images show the results from our SI Fourier-based analysis of 5000, 60 ms frames for the V = 9.91 stellar system TOI-884 (top left), and 3000, 60 ms frames for the stellar systems α Com (middle left) and V819 Her (bottom left). The additional companion seen in V819 Her is not a ghost, see Section 3.2.1. All stars were observed at 832 nm. The right side images show the same data reduced with the MFBD algorithm but using only 1000 for TOI-884 and 500 image frames for α Com and V819 Her. All images are shown on the same logarithmic intensity scale. Note the higher fidelity and lower background (better contrast—see color bar) of the MFBD reconstructed images. We see in the top two SI reconstructions, the typical 180°  ghost, a feature that does not occur in the MFBD methods. The TOI-884 images are shown in a 0.″416 × 0.″416 grid, α Com images are shown in a 1.″248 × 1.″248 grid, and the V819 Her images are shown in a 0.″415 × 0.″415 grid. The TOI-844 and α Com images have a pixel scale of 10.403 mas per pixel whereas the V819 Her images have a pixel scale of 10.393 mas per pixel, and all images are oriented such that north is up and east is to the left.
Paper: High-contrast, High-angular-resolution Optical Speckle Imaging: Uncovering Hidden Stellar Companions
Authors: Steve B. Howell, Arturo O. Martinez, Douglas A. Hope, David R. Ciardi, Stuart M. Jefferies, Fabien R. Baron, Michael B. Lund
Figure caption: We present contrast curves for the binary system, α Com as well as an average contrast curve for ‘Alopeke, obtained using publicly available ‘Alopeke speckle images archived at the NASA Exoplanet Archive. The contrast curves are based on our standard speckle interferometric (SI) pipeline (see Section 2.1) and our new results using MFBD as described herein. The red line shows the 5σ contrast curves from SI using a total of 3 minutes of data for α Com (3000, 60 ms frames). The orange dashed line shows the average SI contrast curve with a 1σ deviation (shaded region) for ‘Alopeke observations from 2019 to mid 2020 (based on data from Scott et al. 2021). The black curve shows the MFBD algorithm results for α Com speckle observations using the best 500 frames of data (i.e., 30 s of data). The blue curve shows a S/N scaled contrast expected from the MFBD algorithm for 3000 best frames. Note the larger contrast achieved with MFBD especially near the inner working angle (i.e., the 8 m diffraction limit). All observations were made at 832 nm. See Section 3.2.2.
Paper: High-contrast, High-angular-resolution Optical Speckle Imaging: Uncovering Hidden Stellar Companions
Authors: Steve B. Howell, Arturo O. Martinez, Douglas A. Hope, David R. Ciardi, Stuart M. Jefferies, Fabien R. Baron, Michael B. Lund
Figure caption: The measured 832 nm contrast curves from Figure 1 using the standard Fourier (SI) reconstruction techniques and using the MFBD reconstruction technique. The vertical dotted green line represents the Rayleigh diffraction limit (1.22λ/D) at 825 nm for an 8 m telescope. The contrast curves are compared to the optical brightness differences between a G0V primary star and the possible range of stellar companions down through the early M-dwarf sequence. Green marks the contrast range of G dwarfs; yellow marks the contrast range of K dwarfs; red marks the contrast range of M dwarfs (Pecaut & Mamajek 2013; Kirkpatrick et al. 2019). With the new MFBD technique and sufficient total integration time, speckle imaging can reach contrast levels sufficient to detect main sequence companions all the way down through the early-to-mid M dwarfs on an 8 m telescope. The stellar companion to TOI-884 is marked with the red star and shows that the companion, because of its angular proximity to the primary star (0.″05 ≈65 au), was barely detected by the traditional speckle interferometric techniques but is easily detected with the MFBD reduction technique developed here.
Paper: High-contrast, High-angular-resolution Optical Speckle Imaging: Uncovering Hidden Stellar Companions
Authors: Steve B. Howell, Arturo O. Martinez, Douglas A. Hope, David R. Ciardi, Stuart M. Jefferies, Fabien R. Baron, Michael B. Lund
Figure caption: We see here, the final MFBD reconstructed images from the right side of Figure 2 after the removal of the residual blur and aberrations from the instrument PSF. Note that the stars are subdiffraction limited and will now yield far better astrometric and photometric information as the collected light has been nearly perfectly placed in the scene. All images are shown on the same logarithmic intensity scale. The TOI-884 image (left) are shown in a 0.″416 × 0.″416 grid, the α Com (middle) image are shown in a 1.″248 × 1.″248 grid, and the V819 Her image (right) are shown in a 0.″415 × 0.″415 grid. The TOI-844 and α Com reconstructed images have a pixel scale of 10.403 mas per pixel whereas the V819 Her images have a pixel scale of 10.393 mas per pixel, and all images are oriented such that north is up and east is to the left. See Section 3.2.
Paper: High-contrast, High-angular-resolution Optical Speckle Imaging: Uncovering Hidden Stellar Companions
Authors: Steve B. Howell, Arturo O. Martinez, Douglas A. Hope, David R. Ciardi, Stuart M. Jefferies, Fabien R. Baron, Michael B. Lund
Figure caption: This figure illustrates some steps in the progress throughout the MFBD reconstructions, starting with a preliminary location and PSF shape estimate and ending with the final reconstructed image. The upper-left image shows (in linear scale) the starting object image for α Com based on the “best” few hundred speckle frames using the shift-and-add method. Note that this example binary, with two nearly equal components, reveals both stars at this step. This would not be the case for a majority of systems, fainter companions would not be detected at this stage. The upper middle and upper right images (in logarithmic scale) show the updates of the deconvolved PSF and object scene as the phase of the images is solved for. The lower image (in logarithmic scale) shows the object once complex variables are used allowing the image amplitudes to be incorporated. All images have a pixel scale of 10.403 mas per pixel and north is up and east to the left.
Paper: High-contrast, High-angular-resolution Optical Speckle Imaging: Uncovering Hidden Stellar Companions
Authors: Steve B. Howell, Arturo O. Martinez, Douglas A. Hope, David R. Ciardi, Stuart M. Jefferies, Fabien R. Baron, Michael B. Lund
Figure caption: The left column is for a generic G0V star at 50 pc and the right column is for a generic G0V star at 150 pc. The top row is the expected detection fractions using the traditional Fourier techniques (SI) and the bottom row is results for the new MFBD technique. The blue and orange histograms are the detected and undetected companion distributions, respectively. The vertical red line marks the 2 yr orbital period position for reference. At 50 pc, the SI technique detects approximately 70% of the expected stellar companions, but at 150 pc, that fraction drops to 60%. MFBD enables the detection of ≳90% of the expected companions even at 150 pc.
Paper: Feasibility of High-resolution Transmission Spectroscopy for Low-velocity Exoplanets
Authors: Connor J. Cheverall, Nikku Madhusudhan
Figure caption: Successful recovery of low-velocity planet signals with varying S/N for each molecule. Shown is the S/N across K p−V sys space when cross-correlating the detrended residuals, first without (left) and then with (right) prior atmospheric model injection, with the relevant atmospheric models. Three, five, and seven principal components were removed in detrending for each of NH3, CH4, and H2O, respectively, in accordance with the ΔCCF metric. Left: without prior injection, no significant signals are seen where we later inject model planetary spectra (marked by crosshairs) to create synthetic data sets, with only a tentative feature seen at V sys ∼20 km s−1 for NH3. Right: the injected signals are recovered, with varying strengths for each molecule, at the correct V sys, with S/N values of 5.0, 4.2, and 2.1 for NH3, CH4, and H2O, respectively. These signals are unconstrained in K p. In each case, the signal has been injected into 21 in-transit spectra with a planetary velocity of K p = 70 km s−1.
Paper: Feasibility of High-resolution Transmission Spectroscopy for Low-velocity Exoplanets
Authors: Connor J. Cheverall, Nikku Madhusudhan
Figure caption: Effect of PCA detrending on the planet signal for different planet orbital velocities and molecules. Here we compare the degradation of NH3 and H2O signals by PCA for a temperate planet such as TOI-732 c (solid) with that for a planet with a higher orbital velocity, e.g., that typical of a hot Jupiter such as HD 189733 b (dashed). The signal is eroded faster for the planet with lower radial velocity change over the transit, as would be expected. The planetary pixel shift, N px, introduced later in Section 3, is the number of instrument pixels by which the planet signal is Doppler shifted during the transit. Note that the absolute signal strength of NH3 is stronger than that for H2O, with all cases here rescaled with respect to their own initial strength.
Paper: Feasibility of High-resolution Transmission Spectroscopy for Low-velocity Exoplanets
Authors: Connor J. Cheverall, Nikku Madhusudhan
Figure caption: Constraining the injected signals in N in−V sys space. The resulting S/N across this space is shown when each of an NH3 (top), CH4 (middle), and an amplified H2O (bottom) signal is injected into 21 in-transit spectra and then recovered, as in Figure 2. For each point in this space the signals have been evaluated at the injection K p of 70 km s−1. The signals are correctly constrained around N in of 21, suggesting that they are indeed planetary rather than derived from telluric, stellar, or spurious features.
Paper: Feasibility of High-resolution Transmission Spectroscopy for Low-velocity Exoplanets
Authors: Connor J. Cheverall, Nikku Madhusudhan
Figure caption: The ΔCCF signal for NH3 after different numbers of principal components have been subtracted from the spectra. Top: for low-velocity planets, in this case N px = 1.4, the main degradation of the planet signal occurs in the center of the transit, with the edges preferentially surviving the successive subtraction of principal components. Strong out-of-transit artifacts are seen. Bottom: for high-velocity planets, e.g., a typical hot Jupiter with N px = 25, the loss of planet signal after application of the PCA algorithm is slower and more equally distributed across the transit. Note that the top and bottom panels are scaled independently for clarity.
Paper: Feasibility of High-resolution Transmission Spectroscopy for Low-velocity Exoplanets
Authors: Connor J. Cheverall, Nikku Madhusudhan
Figure caption: The low-radial-velocity-change planet signals can no longer be recovered when there are no out-of-transit spectra used in the detrending. In each case the planetary signal is injected at K p = 70 km s−1, as in Figure 4, but the detection is no longer seen due to the loss in contrast between the planet signal and telluric/stellar contaminants. Left: for an injection of NH3 at V sys of 0 km s−1, the 12 out-of-transit spectra are removed prior to detrending, leaving only the 21 in-transit spectra. Right: we inject a CH4 signal into all 33 spectra with a V sys of −15 km s−1, such that the transit duration discriminator is removed. Again, the signal recovery is lost in this case.