The Irrepressible Myth of Klein

The Reconstruction-era case of United States v. Klein remains the object of a “cult” among commentators and advocates, who see it as a powerful separation of powers precedent. In fact, Klein is a myth—actually two related myths. One is that it is opaque and meaninglessly indeterminate because, given its confusing and disjointed language, its precise doctrinal contours are indecipherable; the other is that Klein is vigorous precedent, likely to be used by a court to invalidate likely federal legislation. Close analysis of Klein, its progeny, and past scholarship uncovers three identifiable core limitations on congressional control over the workings of federal courts. But close analysis also reveals that these principles are neither exceptional nor vigorous as judicial constraints on congressional power. It is telling that in 140 years, Klein has not been used to invalidate any actual legislation, other than the law at issue in Klein itself. At bottom, Klein becomes the lynchpin for constitutionalizing basic policy preferences against these laws. But this ignores a central distinction between bad policy and unconstitutional policy; we cannot confuse what the Constitution prohibits with bad statesmanship. Couching policy objections in Klein terms does not make the decision any less a constitutional myth

The Discovery of Pulsating Hot Subdwarfs in NGC 2808

We present the results of a Hubble Space Telescope program to search for pulsating hot subdwarfs in the core of NGC 2808. These observations were motivated by the recent discovery of such stars in the outskirts of omega Cen. Both NGC 2808 and omega Cen are massive globular clusters exhibiting complex stellar populations and large numbers of extreme horizontal branch stars. Our far-UV photometric monitoring of over 100 hot evolved stars has revealed six pulsating subdwarfs with periods ranging from 85 to 149 s and UV amplitudes of 2.0 to 6.8%. In the UV color-magnitude diagram of NGC 2808, all six of these stars lie immediately below the canonical horizontal branch, a region populated by the subluminous "blue-hook" stars. For three of these six pulsators, we also have low-resolution far-UV spectroscopy that is sufficient to broadly constrain their atmospheric abundances and effective temperatures. Curiously, and in contrast to the omega Cen pulsators, the NGC 2808 pulsators do not exhibit the spectroscopic or photometric uniformity one might expect from a well-defined instability strip, although they all fall within a narrow band (0.2 mag) of far-UV luminosity.Comment: 5 pages, 1 table, 2 color and 2 grayscale figures. Accepted for publication in The Astrophysical Journal Letter

Quantum physics on a general Hilbert space

Contains fulltext : 170404.pdf (publisher's version ) (Open Access

Just how hot are the ω\omega Centauri extreme horizontal branch pulsators?

Past studies based on optical spectroscopy suggest that the five $\omega$ Cen pulsators form a rather homogeneous group of hydrogen-rich subdwarf O stars with effective temperatures of around 50 000 K. This places the stars below the red edge of the theoretical instability strip in the log $g$ $-$ Teff diagram, where no pulsation modes are predicted to be excited. Our goal is to determine whether this temperature discrepancy is real, or whether the stars' effective temperatures were simply underestimated. We present a spectral analysis of two rapidly pulsating extreme horizontal branch (EHB) stars found in $\omega$ Cen. We obtained Hubble Space Telescope/COS UV spectra of two $\omega$ Cen pulsators, V1 and V5, and used the ionisation equilibrium of UV metallic lines to better constrain their effective temperatures. As a by-product we also obtained FUV lightcurves of the two pulsators. Using the relative strength of the N IV and N V lines as a temperature indicator yields Teff values close to 60 000 K, significantly hotter than the temperatures previously derived. From the FUV light curves we were able to confirm the main pulsation periods known from optical data. With the UV spectra indicating higher effective temperatures than previously assumed, the sdO stars would now be found within the predicted instability strip. Such higher temperatures also provide consistent spectroscopic masses for both the cool and hot EHB stars of our previously studied sample.Comment: 9 pages, accepted for publication in Astronomy and Astrophysic

The Rapidly Rotating, Hydrogen Deficient, Hot Post-Asymptotic Giant Branch Star ZNG 1 in the Globular Cluster M5

We report observations of the hot post-asymptotic giant branch star ZNG 1 in the globular cluster M5 (NGC 5904) with the Far Ultraviolet Spectroscopic Explorer (FUSE). From the resulting spectrum, we derive an effective temperature T_eff = 44300 +/- 300 K, a surface gravity log g = 4.3 +/- 0.1, a rotational velocity v sin i = 170 +/- 20 km/s, and a luminosity log (L/L_sun) = 3.52 +/- 0.04. The atmosphere is helium-rich (Y = 0.93), with enhanced carbon (2.6% by mass), nitrogen (0.51%) and oxygen (0.37%) abundances. The spectrum shows evidence for a wind with terminal velocity near 1000 km/s and an expanding shell of carbon- and nitrogen-rich material around the star. The abundance pattern of ZNG 1 is suggestive of the ``born-again'' scenario, whereby a star on the white-dwarf cooling curve undergoes a very late shell flash and returns to the AGB, but the star's rapid rotation is more easily explained by a previous interaction with a binary companion.Comment: 8 pages, 2 PostScript figures, Latex with emulateapj5. Accepted for publication in ApJ Letter

Do investors understand really dirty surplus?

This study addresses whether firms’ share prices correctly reflect two accounting measures: dirty surplus and really dirty surplus. Dirty surplus is readily observable from the financial statements, but really dirty surplus, which arises from recognizing equity transactions such as employee stock option exercises at other than fair market value, is not. Findings show that dirty surplus and really dirty surplus are irrelevant for forecasting abnormal comprehensive income. However, findings also indicate that investors appear to undervalue really dirty surplus. Hedge returns are insignificant when portfolios are formed based on dirty surplus, but are significantly positive based on really dirty surplus. Really dirty surplus positive hedge returns are robust to a variety of sensitivity tests. Taken together, the findings are consistent with either investors over-valuing firms that have large negative really dirty surplus or really dirty surplus being correlated with an unmodeled risk factor