adsabs/AstroCLIMB huggingface dataset:
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: HST image of LEDA 1313424 (the “Bullseye”), processed by ESA, with additional cropping and contrast adjustments made to highlight some of the low surface brightness structures. We do not use this image for any measurements, but it provides a striking view of the varied rings throughout this system, from red inner rings (where gas may have been evacuated), to blue, highly star-forming rings, to evidence west of the galaxy for a fading, expanded ring at large radius (which has since been spectroscopically confirmed). That faint material extends up to ~70 kpc from the center of the galaxy. The image also captures a clumpy, blue galaxy that appears to have strong starbursting behavior and has a line-of-sight velocity a few hundred km s−1 offset from the Bullseye. While not shown in this work, KCWI spectroscopy of the Bullseye core finds elevated [N II]/Hα ratios suggestive of AGN triggering.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: Unsharp-mask view of the galaxy, with red ellipses overplotted over structures initially identified as rings. Restricted-radius radial profiles were then used in the vicinity of each structure to measure their centroids.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: Smoothed Dragonfly g-band cutout of LEDA 1313424 (left), along with the same image in a larger field of view PSF-matched to WISE W3 (center) and (smoothed) WISE (W3) band imaging (right) of the same region. The box in the center and right panels shows the field of view of the left-hand cutout. The WISE data provide an independent probe of the galactic cirrus distribution and find no evidence for the ringlike structure seen in Dragonfly (though we note that there is subtlety in comparing cirrus probes at different wavelengths, as they trace different mixtures of the dust grain distribution). If the ring structure is indeed extragalactic, it would not be expected to appear in the infrared map, thus providing additional evidence that the cirrus modeling and subtraction presented in Figure 7 are legitimately identifying a ring.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: Surface brightness profile in the g band for LEDA 1313424. We find that the strongest rings (the red ring set and two blue rings) are easily discernible in the profile. Total flux is measured by integrating over the measured profile (and compared with the measured photometry used to derive the stellar mass). We find re = 19.75 kpc and r80 = 36.14 kpc.
Paper: Carving the Edges of the Rocky Planet Population
Authors: Eve J. Lee, James E. Owen
Figure caption: Radius vs. period drawn from the NASA Exoplanet Archive (NASA Exoplanet Archive 2024b) using their default value. We only plot planets with ≤8% error in radius measurement. Top: the blue lines show the minimum survival radius for time-varying B⋆ with B⋆,i =  (100, 30, 10) G for the dashed, dot–dashed, and dotted lines, respectively. All other parameters are set to fiducial values. The red dashed and dot–dashed lines show the radius of the planet corresponding to the maximum mass that survives against tidal decay (Equation (16)) for 5 Gyr around a 1 and 0.5 M⊙ star, respectively. The gray zone is the forbidden region inside which a rocky planet would be tidally disrupted. Bottom: same as the top panel, but now the blue lines correspond to varying stellar mass M⋆ = (1, 0.5, 0.3) M⊙ for the dashed, dot–dashed, and dotted lines, respectively, for B⋆,i = 100 G.
Paper: Carving the Edges of the Rocky Planet Population
Authors: Eve J. Lee, James E. Owen
Figure caption: The distribution of planetary radii after 5 Gyr of evolution from our numerical simulations for a solar-mass star. The left panel includes the influence of photoevaporation only, demonstrating that photoevaporation can create super-Earths with masses >10 M⊕ at periods ≲1 day. The combination of photoevaporation and tidal decay (middle panel) limits the maximum super-Earth mass to ∼10 M⊕. Finally, the combination of photoevaporation, tidal decay, and magnetic drag (right panel) sculpts the close-in super-Earth population, carving demographic features similar to the observed population. The addition of tidal decay does populate the evaporation desert with the odd planet that has retained its H-dominated atmosphere; these planets have been caught spiraling into the host star. The gray zone is the forbidden region inside which a rocky planet would be tidally disrupted. The dashed red and dashed blue lines in the right panel are our tidal and magnetic decay boundaries, respectively (same as those in the top panel of Figure 2). Note the significant drop in planet density inside these boundaries; planets found at shorter periods than these lines are undergoing significant orbital decay on timescales ≲1 Gyr.
Paper: Carving the Edges of the Rocky Planet Population
Authors: Eve J. Lee, James E. Owen
Figure caption: A grand summary highlighting all the physical processes that sculpt the small-planet population in the radius–period space. Plotted in contour is the Gaussian kernel density estimation of Kepler candidates from Data Release 25 (S. E. Thompson et al. 2018). We do not correct for detection biases, as these contours are for illustration purposes. Rocky planets are expected to be found in a region bounded by the evaporation/primordial gap (orange dashed line/light-gray region), tides (red dashed line), and magnetic drag (blue dashed line). All the boundaries drawn in this figure assume a system age of 5 Gyr, M⋆ = M⊙, and B⋆,i = 100 G. Varying these stellar parameters can widen or shrink the allowable region of surviving rocky planets.
Paper: Carving the Edges of the Rocky Planet Population
Authors: Eve J. Lee, James E. Owen
Figure caption: Top: orbital evolution of rocky planets under magnetic drag. Each curve terminates when the Roche radius is reached. Squares indicate the point beyond which the Joule heating exceeds the planet’s gravitational binding energy (see text for detail). The black circle represents the orbital period and the age of the disintegrating planet Kepler-1520 b (S. Rappaport et al. 2012; T. D. Morton et al. 2016). Bottom: the Joule heat flux deposited into the planet along the orbital period evolution.
Paper: Carving the Edges of the Rocky Planet Population
Authors: Eve J. Lee, James E. Owen
Figure caption: Same as Figure 1, but with the upper limit of the lowest stellar mass bin adjusted to 0.35 M⊙ and the lower limit of the highest stellar mass bin adjusted to 1.2 M⊙.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: Summary of the cirrus modeling and subtraction procedure. In the top row, we show a wide-field view of the region, with the original Dragonfly g-band image (left), source flux model constructed by mrf (center), and cirrus model created using the mrf-subtracted image (right). A white box in each panel identifies the location of LEDA 1313424 in the field. In the bottom row, we show zoomed-in panels of the apertures shown in the top row of the mrf-filtered g-band image (left) and residual after cirrus modeling, subtraction, and smoothing (right), both with an overlay of the KCWI pointing in white within which the Hα detections were made at the redshift of LEDA 1313424. Residuals from mrf subtraction were masked; these mask locations are shown in the left-hand image as semitransparent overlays. The maskfill package was used to fill in these source masks on the right. We find clear evidence for ring 2, which shares a similar position angle and axis ratio to the inner rings. We mark a nominal matched ellipse to this ring structure in white.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: KCWI moment zero map of the dwarf and ring of the Bullseye (center panel), with 1D spectra extracted from various apertures shown in panels (A)–(J). To guide the eye, we show the regions targeted by each extraction over the ESA-created HST image in the corner of the center panel. In all spectra, a vertical blue dashed line marks the rough velocity of the Bullseye galaxy as traced by the narrow line emission in the ring feature in aperture (F), while a dashed red line marks the rough velocity of the dwarf galaxy as traced by the narrow component of emission in the central pointing in aperture (J). These extractions trace a disturbed and complex ionization and kinematic state for the gas in the dwarf and between the dwarf and the Bullseye. In particular, we note that broad (σ > 500 km s−1) components of emission exist both in relative spatial isolation (as in apertures (D), (E), and (F)) and blended with narrow line emission (as in apertures (A), (H), and (J)). The velocities of this gas span the full wavelength range between the dwarf and the Bullseye and, critically, do not appear significantly outside this velocity region. Paired with the non-Gaussian shape of the broad line emission, these spectra are highly suggestive of either gas being stripped from the dwarf and trailing behind or gas liberated from LEDA 1313424 and moving toward the dwarf, or both. It is challenging to explain the observed lines (and line ratios) in any scenario in which the dwarf is not the impacting galaxy.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: Analytic ring theory makes predictions for the ratio of successive ring radii; thus, if one assumes a particular ring number for a particular measured ring, all other ring positions can be predicted. Here, we show the measured ring radii as a function of such a prediction, in which the outermost narrow star-forming ring is assumed to be ring 3 (black), or several other possible ring numbers (1, 2, 4, and 5) in colors. From this comparison, it is clear that the interpretation of the outermost narrow star-forming ring as ring 3 is the most consistent with the data; the black dotted line shows the 1:1 relation. It is further clear that the predictions in this case are remarkably close to the measured values across all detected rings. Note that we detect a structure (ring 2) beyond the outermost narrow star-forming ring, which precludes it being ring 1, via Dragonfly Telephoto Array imaging (discussed in Section 2.2.2). In all cases, the predicted ratios are based on an assumption of an FRC; in this case, inner rings (beyond 3) are expected to overlap, and thus the offset from the 1:1 relation for some inner rings could be a result of measuring the outer or inner edges of broad, overlapping rings.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: Composite HST color image of LEDA 1313424 (the “Bullseye”) created by the authors using the F475W and F814W imaging and placed on the world coordinate system. Here we demarcate a white box over the patch of blue emission seen to the west of the galaxy to indicate the pointing for KCWI, which we use to spectroscopically confirm the redshift of this emission. All measurements presented in this work were made on the science-calibrated images used to produce this composite.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: Zoom-in of the region targeted by KCWI, with the large slicer (20﹩\mathop{.}\limits^{\unicode{x02033}}﹩4 × 33″) targeted field of view shown at left. On the right, we show a moment zero map of the KCWI data cube constructed for a narrow velocity range around the ~11,816 km s−1 recession velocity of LEDA 1313424, smoothed with a Gaussian kernel with σ = 1.8. In white boxes, we show several regions with identified emission line detections with velocities consistent with LEDA 1313424; these boxes are replicated on the left to show from where the emission is originating. The 1D spectra extracted from these regions can be found in Figure 6.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: Mean-collapsed 1D spectra extracted from the regions identified in Figure 5 in the observed (heliocentric, vacuum) frame. Raw extracted spectra are shown in gray; a binned spectrum (two- or three-element average) is shown in black, with bad pixels masked, and a vertical dashed line indicates the expected Hα location for gas with an identical recession velocity to LEDA 1313424. We find several clear detections of Hα emission within the KCWI footprint over the patch of emission in the outskirts of the Bullseye that span a small velocity range around the galaxy's recession velocity.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: Measured H I/stellar mass relations used in V. Parkash et al. (2018) from samples selected using stellar mass (blue shaded region), H I properties (orange line and shaded region), and morphology (spirals; green shaded region), as well as a relation from N. Maddox et al. (2016; red dotted line). LEDA 1313424 and Malin I are shown in this space as individual stars. We find that both galaxies are relatively rich in H I for their stellar masses, ~1σ or more above the known relations.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: H I spectrum (gray) of LEDA 1313424 retrieved from the ALFALFA survey (M. P. Haynes et al. 2011), with a boxcar smoothed version overlaid in black for clarity. The galaxy has a recognizable double-horned feature in H I with a typical rotation velocity on the order of 370 km s−1 (correcting for inclination). Using the spectrum, we estimate the H I mass of LEDA 1313424 using the shaded region.
Paper: The Bullseye: HST, Keck/KCWI, and Dragonfly Characterization of a Giant Nine-ringed Galaxy
Authors: Imad Pasha, Pieter G. van Dokkum, Qing Liu, 青 刘, William P. Bowman, Steven R. Janssens, Michael A. Keim, Chloe Neufeld, Roberto Abraham
Figure caption: Overview of the ring characterization procedure for rings 3–10. In the left columns, we show the unsharp-mask image of the inner galaxy, masked to the span in θ over which we determined the profile, if relevant. Overplotted are the annuli used for construction of the profile. In the right columns are the extracted profiles, with centroids denoted as calculated from within the FWHM of each peak.
Paper: Carving the Edges of the Rocky Planet Population
Authors: Eve J. Lee, James E. Owen
Figure caption: Planet mass vs. orbital period for different host star masses, drawn from the NASA Exoplanet Archive (NASA Exoplanet Archive 2024a) using their default value. We only plot planets with radii ≤2 R⊕, period  <20 days, and ≤25% error in mass measurement. Blue region: maximum mass for complete photoevaporation with evaporation time spanning 9–14 Gyr, 4–14 Gyr, 2–14 Gyr, and 2–7 Gyr for each stellar mass bin from lightest to heaviest (the choice of the age is from visual inspection of Figure 5 of E. A. Petigura et al. 2022). Red region: characteristic maximum mass for tidal decay under dynamical tides for the same range of ages as the blue region. Red dotted line: like the red region, but for constant ﹩{Q}_{\star }^{{\prime} }=1{0}^{7}﹩ for a fixed age of 5 Gyr, drawn for a reference. The gray zone is the forbidden zone due to Roche lobe overflow. The four stellar mass bins are chosen so that the number of planets within each bin is approximately uniform while ensuring that the bin boundaries do not blur the stellar spectral types too much. The effect of choosing different bins is discussed in Appendix A.
Paper: Nonstop Variability of Sgr A* Using JWST at 2.1 and 4.8 μm Wavelengths: Evidence for Distinct Populations of Faint and Bright Variable Emission
Authors: F. Yusef-Zadeh, H. Bushouse, R. G. Arendt, M. Wardle, J. M. Michail, C. J. Chandler
Figure caption: Top left: a scatter plot of the F210M and F480M flux densities on all days overlaid with loci of constant spectral index. The magenta line is a broken linear fit to the data, with parameters listed in Table 6. The slope for the fainter data points corresponds to a spectral index α ∼ −1.58, whereas the slope for the brighter data points, the spectral index flattens to α ∼ −0.85. The change in the slope suggests two different populations with different spectral indices. Top right: light curves of Sgr A* at 2.1 μm for all epochs. Middle left: the spectral index of Sgr A* as a function 2.1 μm flux density for all six epochs of observations. Middle right: the spectral index evolution for all six epochs. The colors correspond to the times indicated for each epoch. Bottom: the spectral index vs. 2.1 μm flux density on day 7 if the 4.8 μm subtracted background is reduced by 1 and 2 mJy. Given that the background 4.8 μm flux is more likely to be contaminated by nearby stars than the 2.2 μm flux of Sgr A*, the positive spectral index of faint variable emission (shown in blue) disappears when the 4.8 μm flux is increased by 1 mJy. However, the bright flare's spectral indices and the trend are not affected by the background change.
Paper: Nonstop Variability of Sgr A* Using JWST at 2.1 and 4.8 μm Wavelengths: Evidence for Distinct Populations of Faint and Bright Variable Emission
Authors: F. Yusef-Zadeh, H. Bushouse, R. G. Arendt, M. Wardle, J. M. Michail, C. J. Chandler
Figure caption: Similar to Figure 7, where data for all days are shown. The top left panel shows the colored variation of the 4.8 μm flux against the 2.1 μm flux density. The top right panel shows light curves of Sgr A* in color at 2.1 μm. The bottom left panel shows the spectral index of Sgr A* in color as a function of 2.1 μm flux density. The bottom right panel shows the spectral index as a function of each time in color.
Paper: Nonstop Variability of Sgr A* Using JWST at 2.1 and 4.8 μm Wavelengths: Evidence for Distinct Populations of Faint and Bright Variable Emission
Authors: F. Yusef-Zadeh, H. Bushouse, R. G. Arendt, M. Wardle, J. M. Michail, C. J. Chandler
Figure caption: Left two columns: the variation of the spectral index as a function of F480M flux density is shown for five flares. The colors denote time. The variations of the spectral index trace counterclockwise loops. Right two columns: the modeled time delays and loop diagrams are interpreted to be due to synchrotron cooling, as the 4.8 μm emission lags in time behind the 2.1 μm emission. These fits provide the physical characteristics of individual flares (see Table 7).
Paper: Nonstop Variability of Sgr A* Using JWST at 2.1 and 4.8 μm Wavelengths: Evidence for Distinct Populations of Faint and Bright Variable Emission
Authors: F. Yusef-Zadeh, H. Bushouse, R. G. Arendt, M. Wardle, J. M. Michail, C. J. Chandler
Figure caption: Using all seven epochs of observations, histograms of the flux distribution of Sgr A* at 2.1 and 4.8 μm are displayed in the top left and right panels, respectively. LN (light green line), LN-plus-power-law (dark green line), and two-LN (dashed green line) distribution fits to the histograms are shown. The two-LN and LN-plus-power-law fits are reasonable representations of weak fluctuations at 4.8 and 2.1 μm, respectively. Other distributions give failed solutions to fit strong fluxes (see Table 3 and text). The histograms indicate two populations of the variable emission. The ﹩1\sigma =\sqrt{N}﹩ error bars are shown on the histogram bins. The bottom panel shows the fraction of time at which Sgr A* is observed below a given flux density.
Paper: Nonstop Variability of Sgr A* Using JWST at 2.1 and 4.8 μm Wavelengths: Evidence for Distinct Populations of Faint and Bright Variable Emission
Authors: F. Yusef-Zadeh, H. Bushouse, R. G. Arendt, M. Wardle, J. M. Michail, C. J. Chandler
Figure caption: Power spectra of the temporal variations of Sgr A* on a log-frequency scale in the F210M (blue) and F480M (red) bands are presented for each epoch of observation. The data for each epoch are fitted with broken power-law trends over the frequency ranges indicated by the solid lines with a transition frequency where the power-law distribution becomes flat at low f0 and high frequencies f1/2 (see Table 5). The power-law index n is indicated in the figure. These plots show evidence of Sgr A*’s variability, displaying two different statistics on short- and long-term timescales at frequencies f ≥ f0 and f < f0, respectively. Note that the transition frequency f0 changes in every epoch, supporting long-term quiescent variability of Sgr A*, though longer continuous observations are needed to confirm this result.
Paper: Nonstop Variability of Sgr A* Using JWST at 2.1 and 4.8 μm Wavelengths: Evidence for Distinct Populations of Faint and Bright Variable Emission
Authors: F. Yusef-Zadeh, H. Bushouse, R. G. Arendt, M. Wardle, J. M. Michail, C. J. Chandler
Figure caption: Values of the time derivative of day 6 data normalized by the flux density as a function of time are presented in the top and and bottom panels. Three examples in which values are highest are near 9.5, 9.85, and 10.3 UT, showing a change in the flux density by a factor of e in ∼2−3 minutes.
Paper: Nonstop Variability of Sgr A* Using JWST at 2.1 and 4.8 μm Wavelengths: Evidence for Distinct Populations of Faint and Bright Variable Emission
Authors: F. Yusef-Zadeh, H. Bushouse, R. G. Arendt, M. Wardle, J. M. Michail, C. J. Chandler
Figure caption: Cross-correlation of the Sgr A* light curves in the F210M and F480M bands as a function of time are shown for each of the six epochs of observations. Epochs 1, 2, and 4 are displayed in the top three panels, whereas epochs 5, 6, and 7 are displayed in the bottom panels. The cross-correlations indicate time delays in the range between 3 and 40 s. Positive Δt, as shown in red in each figure, corresponds to F210M variations preceding those at F480M.
Paper: Nonstop Variability of Sgr A* Using JWST at 2.1 and 4.8 μm Wavelengths: Evidence for Distinct Populations of Faint and Bright Variable Emission
Authors: F. Yusef-Zadeh, H. Bushouse, R. G. Arendt, M. Wardle, J. M. Michail, C. J. Chandler
Figure caption: Same as Figure 7 but showing day 2 data.