597 research outputs found
Marriage as Black Citizenship?
The narrative of black marriage as citizenship enhancing has been pervasive in American history. As we mark the fiftieth anniversary of the Moynihan Report and prepare to celebrate the 150th anniversary of Thirteenth Amendment, this Article argues that this narrative is one that we should resist. The complete story of marriage is one that involves racial subordination and caste. Even as the Supreme Court stands to extend marriage rights to LGBT couples, the Article maintains that we should embrace nonmarriage as a legitimate frame for black loving relationships—gay or straight. Nonmarriage might do just as much, if not more, to advance black civil rights. Part I explores marriage’s role in racial subordination by looking at the experiences of African Americans, as well as Native Americans, Puerto Ricans, and Asian Americans. Drawing on institutional structure analyses, it then considers how legal marriage has “married” Blacks to second-class citizenship. Part II explores the current place of marriage in African America. It argues that, while the regulation of black loving relationships today differs dramatically from what we saw in earlier times, family law often has a punitive effect on such American families. Part III contemplates the benefits of adopting a focus on nonmarriage. It contends that meeting black families where they are holds the most potential for progress in addressing the structural barriers to success faced by those families. The Article ends with a “call to action” for legal scholars and others concerned about black families and citizenship. It maps a broad agenda for exploring in earnest the potential that supporting and valuing the existing networks, arrangements, and norms regarding gender and caretaking in African America has for promoting black citizenship and equality in the twenty-first century
Parenting While Black
Changes in law and policy—not to mention developments such as the COVID-19 pandemic and its devastating effects on families—raise important questions about how to define parental rights and how to best support parents and children during these challenging times. The Symposium also presented important questions about issues of race, gender, sexuality, and class in our modern context. Even more salient in this space are issues of race. Here, as in other contexts, Black families, like my grandmother’s and so many others, are the “canaries in the mine.” Their experiences provide us with important insight into the signs of danger facing Black and Brown families. To that extent, the concerns of families, like my grandmother’s, should be at the center of our discussion around families and the challenges they face in this moment. This Essay intervenes in the conversation hosted by the Fordham Law Review by focusing on issues of race, which, as I have indicated elsewhere, remain underexplored in family law scholarship.1 More specifically, it endeavors to give greater context to the term “parenting while Black,” which I utilized in the narrative that launched this iniquity. In the wake of George Floyd’s death at the hands of police in 2020,2 people of all walks of life are all too familiar with the phrase “driving, or even walking, while Black.”3 These phrases reference the scores of Black and Brown people killed or badly injured at the hands of white law enforcement officers, often when the need for such action was plainly unwarranted.4 In deploying the term “parenting while Black,” I mean to invoke not only the criminal justice context, but also all the systems that inform the functioning and well-being of families of color. Enumerating such systems provides us with a deeper appreciation of the obstacles that parents of color must navigate in trying to provide for their children
New pathway to bypass the 15O waiting point
We propose the sequential reaction process
O(,)O as a new pathway to bypass of the
O waiting point. This exotic reaction is found to have a surprisingly
high cross section, approximately 10 times higher than the
O(,)O. These cross sections were calculated after
precise measurements of energies and widths of the proton-unbound F low
lying states, obtained using the H(O,p)O reaction. The large
cross section can be understood to arise from the more
efficient feeding of the low energy wing of the ground state resonance by the
gamma decay. The implications of the new reaction in novae explosions and X-ray
bursts are discussed.Comment: submitte
An all-solid-state laser source at 671 nm for cold atom experiments with lithium
We present an all solid-state narrow line-width laser source emitting
output power at delivered in a
diffraction-limited beam. The \linebreak source is based on a
fre-quency-doubled diode-end-linebreak pumped ring laser operating on the
transition in Nd:YVO. By using
periodically-poled po-tassium titanyl phosphate (ppKTP) in an external build-up
cavity, doubling efficiencies of up to 86% are obtained. Tunability of the
source over is accomplished. We demonstrate the suitability of
this robust frequency-stabilized light source for laser cooling of lithium
atoms. Finally a simplified design based on intra-cavity doubling is described
and first results are presented
Probing Nuclear forces beyond the drip-line using the mirror nuclei N and F
Radioactive beams of O and O were used to populate the resonant
states 1/2, 5/2 and in the unbound F and F
nuclei respectively by means of proton elastic scattering reactions in inverse
kinematics. Based on their large proton spectroscopic factor values, the
resonant states in F can be viewed as a core of O plus a proton
in the 2s or 1d shell and a neutron in 1p. Experimental
energies were used to derive the strength of the 2s-1p and
1d-1p proton-neutron interactions. It is found that the former
changes by 40% compared with the mirror nucleus N, and the second by
10%. This apparent symmetry breaking of the nuclear force between mirror nuclei
finds explanation in the role of the large coupling to the continuum for the
states built on an proton configuration.Comment: 6 pages, 3 figures, 2 tables, accepted for publication as a regular
article in Physical Review
Transverse sphericity of primary charged particles in minimum bias proton-proton collisions at , 2.76 and 7 TeV
Measurements of the sphericity of primary charged particles in minimum bias
proton--proton collisions at , 2.76 and 7 TeV with the ALICE
detector at the LHC are presented. The observable is linearized to be collinear
safe and is measured in the plane perpendicular to the beam direction using
primary charged tracks with GeV/c in . The
mean sphericity as a function of the charged particle multiplicity at
mid-rapidity () is reported for events with different
scales ("soft" and "hard") defined by the transverse momentum of the leading
particle. In addition, the mean charged particle transverse momentum versus
multiplicity is presented for the different event classes, and the sphericity
distributions in bins of multiplicity are presented. The data are compared with
calculations of standard Monte Carlo event generators. The transverse
sphericity is found to grow with multiplicity at all collision energies, with a
steeper rise at low , whereas the event generators show the
opposite tendency. The combined study of the sphericity and the mean with multiplicity indicates that most of the tested event generators
produce events with higher multiplicity by generating more back-to-back jets
resulting in decreased sphericity (and isotropy). The PYTHIA6 generator with
tune PERUGIA-2011 exhibits a noticeable improvement in describing the data,
compared to the other tested generators.Comment: 21 pages, 9 captioned figures, 3 tables, authors from page 16,
published version, figures from
http://aliceinfo.cern.ch/ArtSubmission/node/308
<i>Gaia</i> Data Release 1. Summary of the astrometric, photometric, and survey properties
Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7.
Aims. A summary of Gaia DR1 is presented along with illustrations of the scientific quality of the data, followed by a discussion of the limitations due to the preliminary nature of this release.
Methods. The raw data collected by Gaia during the first 14 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium (DPAC) and turned into an astrometric and photometric catalogue.
Results. Gaia DR1 consists of three components: a primary astrometric data set which contains the positions, parallaxes, and mean proper motions for about 2 million of the brightest stars in common with the HIPPARCOS and Tycho-2 catalogues – a realisation of the Tycho-Gaia Astrometric Solution (TGAS) – and a secondary astrometric data set containing the positions for an additional 1.1 billion sources. The second component is the photometric data set, consisting of mean G-band magnitudes for all sources. The G-band light curves and the characteristics of ∼3000 Cepheid and RR-Lyrae stars, observed at high cadence around the south ecliptic pole, form the third component. For the primary astrometric data set the typical uncertainty is about 0.3 mas for the positions and parallaxes, and about 1 mas yr−1 for the proper motions. A systematic component of ∼0.3 mas should be added to the parallax uncertainties. For the subset of ∼94 000 HIPPARCOS stars in the primary data set, the proper motions are much more precise at about 0.06 mas yr−1. For the secondary astrometric data set, the typical uncertainty of the positions is ∼10 mas. The median uncertainties on the mean G-band magnitudes range from the mmag level to ∼0.03 mag over the magnitude range 5 to 20.7.
Conclusions. Gaia DR1 is an important milestone ahead of the next Gaia data release, which will feature five-parameter astrometry for all sources. Extensive validation shows that Gaia DR1 represents a major advance in the mapping of the heavens and the availability of basic stellar data that underpin observational astrophysics. Nevertheless, the very preliminary nature of this first Gaia data release does lead to a number of important limitations to the data quality which should be carefully considered before drawing conclusions from the data
Centrality dependence of charged particle production at large transverse momentum in Pb-Pb collisions at TeV
The inclusive transverse momentum () distributions of primary
charged particles are measured in the pseudo-rapidity range as a
function of event centrality in Pb-Pb collisions at
TeV with ALICE at the LHC. The data are presented in the range
GeV/ for nine centrality intervals from 70-80% to 0-5%.
The Pb-Pb spectra are presented in terms of the nuclear modification factor
using a pp reference spectrum measured at the same collision
energy. We observe that the suppression of high- particles strongly
depends on event centrality. In central collisions (0-5%) the yield is most
suppressed with at -7 GeV/. Above
GeV/, there is a significant rise in the nuclear modification
factor, which reaches for GeV/. In
peripheral collisions (70-80%), the suppression is weaker with almost independently of . The measured nuclear
modification factors are compared to other measurements and model calculations.Comment: 17 pages, 4 captioned figures, 2 tables, authors from page 12,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/284
Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at TeV
The elliptic, , triangular, , and quadrangular, , azimuthal
anisotropic flow coefficients are measured for unidentified charged particles,
pions and (anti-)protons in Pb-Pb collisions at TeV
with the ALICE detector at the Large Hadron Collider. Results obtained with the
event plane and four-particle cumulant methods are reported for the
pseudo-rapidity range at different collision centralities and as a
function of transverse momentum, , out to GeV/.
The observed non-zero elliptic and triangular flow depends only weakly on
transverse momentum for GeV/. The small dependence
of the difference between elliptic flow results obtained from the event plane
and four-particle cumulant methods suggests a common origin of flow
fluctuations up to GeV/. The magnitude of the (anti-)proton
elliptic and triangular flow is larger than that of pions out to at least
GeV/ indicating that the particle type dependence persists out
to high .Comment: 16 pages, 5 captioned figures, authors from page 11, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/186
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