4mu spectra of AGB stars I: Observations

We present times series of high resolution spectra of AGB variables at 4mu. Line profiles from the major contributors to the spectra of oxygen rich stars at 4mu, OH, H$_2$O, HCl and SiO, are examined. The velocity as well as shape variations of these profiles with time are discussed. The line profiles investigated frequently have emission and multiple absorption components. The changes with time of the 4mu region lines do not always follow the cyclic variability seen in NIR spectra and in the photometric light curve. We interpret and discuss the results qualitatively considering comparing the spectral variability with that of the well behaved 1.6mu region and of dynamical model atmospheres. Miras and semiregular variables are compared. The origins of non-periodic behavior are discussed, including the role of spatial inhomogeneities in the stellar atmosphere.Comment: 14 pages, 12 figures, accepted for publication in A&

Small carbon chains in circumstellar envelopes

Observations were made for a number of carbon-rich circumstellar envelopes using the Phoenix spectrograph on the Gemini South telescope to determine the abundance of small carbon chain molecules. Vibration-rotation lines of the $\nu_{3}$ antisymmetric stretch of C$_{3}$ near 2040 cm$^{-1}$ (4.902 $\mu$m) have been used to determine the column density for four carbon-rich circumstellar envelopes: CRL 865, CRL 1922, CRL 2023 and IRC +10216. We additionally calculate the column density of C$_{5}$ for IRC +10216, and provide an upper limit for 5 more objects. An upper limit estimate for the C$_{7}$ column density is also provided for IRC+10216. A comparison of these column densities suggest a revision to current circumstellar chemical models may be needed

How states learn from the success or failure of other states’ laws in federal courts.

Why make the same mistakes as those who have gone before you? In new research into state lawmaking, Rachael K. Hinkle finds that legislators often put that principle into practice. She finds that when the Supreme Court rules that a state’s law is constitutional, it is 27 percent more likely that another state will adopt that same type of law. In addition, using software originally designed to detect plagiarism, she also uncovers that these other states will borrow up to 7 percent of the law’s text, a probability which triples if a state’s own federal circuit court declares the law to be constitutional

The Role of the U.S. Courts of Appeals in Legal Development: An Empirical Analysis

What are the causes and consequences of legal development? In recent years courts scholars have begun to address these broad and challenging questions, yet there is still much work to be done. The intermediate level of the federal court system: a.k.a., circuit courts) provides an institutional context replete with opportunities to extend our theoretical and empirical understanding of legal development. My dissertation takes advantage of these opportunities in three ways. First, I explore legal constraint by comparing citation to and treatment of circuit court precedents. A precedent is binding in its own circuit, but merely persuasive in other circuits. Consequently, if law constrains judges the effect of ideology on how a precedent is treated should be significantly less when it is considered in its own circuit than when considered by a sister circuit. Second, I investigate the nuances of a circuit\u27s citation to its own binding precedent to determine how it is influenced by strategic anticipation of whether a case will be reviewed and overturned by the entire circuit. Third, I examine the impact of federal courts on state policy discussion, positing that both adoption and content of a policy will be influenced by federal court rulings on the constitutionality of a previously adopted statute

Rachael K. Hinkle, Unintended Consequences. How the Publication Norm as a Tool of Compromise Reduces the Influence of Female and Minority Judges

Even when women and people of color achieve positions of political power, that does not guarantee they will be able to wield the same amount of influence as similarly-situated white men. Institutional norms may combine with social constructions of difference to create a system in which power is distributed disproportionately. Such a pattern is evident in the U.S. Courts of Appeals. Benign procedural practices and laudable deliberative processes combine with divergent viewpoints generated by fundamentally different social experiences to create a system in which power is exercised unequally

Fluorine in the solar neighborhood - is it all produced in AGB-stars?

The origin of 'cosmic' fluorine is uncertain, but there are three proposed production sites/mechanisms: AGB stars, $\nu$ nucleosynthesis in Type II supernovae, and/or the winds of Wolf-Rayet stars. The relative importance of these production sites has not been established even for the solar neighborhood, leading to uncertainties in stellar evolution models of these stars as well as uncertainties in the chemical evolution models of stellar populations. We determine the fluorine and oxygen abundances in seven bright, nearby giants with well-determined stellar parameters. We use the 2.3 $\mu$m vibrational-rotational HF line and explore a pure rotational HF line at 12.2 $\mu$m. The latter has never been used before for an abundance analysis. To be able to do this we have calculated a line list for pure rotational HF lines. We find that the abundances derived from the two diagnostics agree. Our derived abundances are well reproduced by chemical evolution models only including fluorine production in AGB-stars and therefore we draw the conclusion that this might be the main production site of fluorine in the solar neighborhood. Furthermore, we highlight the advantages of using the 12 $\mu$m HF lines to determine the possible contribution of the $\nu$-process to the fluorine budget at low metallicities where the difference between models including and excluding this process is dramatic