Permanent Legal Immigration to the United States: Policy Overview

Four major principles currently underlie U.S. policy on legal permanent immigration: the reunification of families, the admission of immigrants with needed skills, the protection of refugees, and the diversity of admissions by country of origin. These principles are embodied in federal law, the Immigration and Nationality Act (INA) first codified in 1952. The Immigration Amendments of 1965 replaced the national origins quota system (enacted after World War I) with per-country ceilings, and the statutory provisions regulating permanent immigration to the United States were last revised significantly by the Immigration Act of 1990. The critiques of the permanent legal immigration system today are extensive, but there is no consensus on the specific direction the reforms of the law should take. As the Congress considers comprehensive immigration reform (CIR), many maintain that revision of the legal immigration system should be one of the major components of a CIR proposal. This primer on legal permanent immigration law, policies, and trends provides a backdrop for the policy options and debates that may emerge as Congress considers a revision of the legal immigration system

A Primer on U.S. Immigration Policy

[Excerpt] This report provides a broad overview of U.S. immigration policy. The first section addresses policies governing how foreign nationals enter the United States either to reside permanently or to stay temporarily. Related topics within this section include visa issuance and security, forms of quasi-legal status, and naturalization. The second section discusses enforcement policies both for excluding foreign nationals from admission into the United States, as well as for detaining and removing those who enter the country unlawfully or who enter lawfully but subsequently commit crimes that make them deportable. The section also covers worksite enforcement and immigration fraud. The third section addresses policies for unauthorized aliens residing in the United States. While intended to be comprehensive, this primer may omit some immigration-related topics. It does not discuss policy issues or congressional concerns about specific immigration-related policies and programs

Permanent Employment-Based Immigration and the Per-country Ceiling

[Excerpt] The Immigration and Nationality Act (INA) specifies a complex set of categories and numerical limits for admitting lawful permanent residents (LPRs) to the United States that includes economic priorities among the admission criteria. These priorities are addressed primarily through the employment-based immigration system, which consists of five preference categories. Each preference category has specific eligibility criteria; numerical limits; and, in some cases, distinct application processes. The INA allocates 140,000 visas annually for all five employment-based LPR categories, roughly 12% of the 1.1 million LPRs admitted in FY2017. The INA further limits each immigrant-sending country to an annual maximum of 7% of all employment-based LPR admissions, known as the per-country ceiling, or “cap.” Prospective employment-based immigrants follow two administrative processing trajectories depending on whether they apply from overseas as “new arrivals” seeking LPR status or from within the United States seeking to adjust to LPR status from a temporary status that they currently possess. While some prospective employment-based immigrants can self-petition, most require U.S. employers to petition on their behalf. In both cases, the Department of State (DOS) is responsible for allocating the correct number of employment-based immigrant “visa numbers” or slots, according to numerical limits and the per-country ceiling specified in the INA. This report reviews the employment-based immigration process by examining six pools of pending petitions and applications, representing prospective employment-based immigrants and any accompanying family members at different stages of the LPR process. While four of these pools represent administrative processing queues, two result from the INA’s numerical limitations on employment-based immigration and the per-country ceiling

Permanent Legal Immigration to the United States: Policy Overview

[Excerpt] Four major principles currently underlie U.S. policy on legal permanent immigration: the reunification of families, the admission of immigrants with needed skills, the protection of refugees and asylees, and the diversity of immigrants by country of origin. These principles are embodied in the Immigration and Nationality Act (INA) and are reflected in different components of permanent immigration. Family reunification occurs primarily through family sponsored immigration. U.S. labor market contribution occurs through employment based immigration. Humanitarian assistance occurs primarily through the U.S. refugee and asylee programs. Origin country diversity is addressed through the Diversity Immigrant Visa

Effects of dust absorption on spectroscopic studies of turbulence

We study the effect of dust absorption on the recovery velocity and density spectra as well as on the anisotropies of magnetohydrodynamic turbulence using the Velocity Channel Analysis (VCA), Velocity Coordinate Spectrum (VCS) and Velocity Centroids. The dust limits volume up to an optical depth of unity. We show that in the case of the emissivity proportional to the density of emitters, the effects of random density get suppressed for strong dust absorption intensity variations arise from the velocity fluctuations only. However, for the emissivity proportional to squared density, both density and velocity fluctuations affect the observed intensities. We predict a new asymptotic regime for the spectrum of fluctuations for large scales exceeding the physical depths to unit optical depth. The spectrum gets shallower by unity in this regime. In addition, the dust absorption removes the degeneracy resulted in the universal $K^{-3}$ spectrum of intensity fluctuations of self-absorbing medium reported by Lazarian \& Pogosyan. We show that the predicted result is consistent with the available HII region emission data. We find that for sub-Alfv\'enic and trans-Alfv\'enic turbulence one can get the information about both the magnetic field direction and the fundamental Alfv\'en, fast and slow modes that constitute MHD turbulence.Comment: Published in MNRAS, minor changes to match the published versio

The President’s Immigration Accountability Executive Action of November 20, 2014: Overview and Issues

[Excerpt] On November 20, 2014, President Obama announced his Immigration Accountability Executive Action which revises some U.S. immigration policies and initiates several programs, including a revised border security policy for the Southwest border; deferred action programs for some unauthorized aliens; revised interior enforcement priorities; changes to aid the entry of skilled workers; the promotion of immigrant integration and naturalization; and several other initiatives the President indicated would improve the U.S. immigration system. The most controversial among these provisions will grant deferred action to as many as 5 million unauthorized aliens. The President announced the executive action through ten Department of Homeland Security (DHS) memoranda, two White House memoranda, and three Department of Labor (DOL) fact sheets. According to the President, the actions were taken in response to the absence of legislation addressing major problems within the immigration system. The President has stated that his actions are temporary, and that his successor can rescind them. Those opposed to the executive actions argue they were taken largely for political purposes. They contend that once granted, such temporary measures would be difficult to revoke. Separately, a debate has arisen as to whether the President has the legal authority to take such actions, with the Administration and others arguing the President’s actions fall within his authority, and many in Congress arguing the President has overstepped it. That debate and its attendant legal questions are beyond the scope of this report. As the Administration proceeds to implement the executive actions, some in Congress have vowed to halt some or all of them

From Discrete Hopping to Continuum Modeling on Vicinal Surfaces with Applications to Si(001) Electromigration

Coarse-grained modeling of dynamics on vicinal surfaces concentrates on the diffusion of adatoms on terraces with boundary conditions at sharp steps, as first studied by Burton, Cabrera and Frank (BCF). Recent electromigration experiments on vicinal Si surfaces suggest the need for more general boundary conditions in a BCF approach. We study a discrete 1D hopping model that takes into account asymmetry in the hopping rates in the region around a step and the finite probability of incorporation into the solid at the step site. By expanding the continuous concentration field in a Taylor series evaluated at discrete sites near the step, we relate the kinetic coefficients and permeability rate in general sharp step models to the physically suggestive parameters of the hopping models. In particular we find that both the kinetic coefficients and permeability rate can be negative when diffusion is faster near the step than on terraces. These ideas are used to provide an understanding of recent electromigration experiment on Si(001) surfaces where step bunching is induced by an electric field directed at various angles to the steps.Comment: 10 pages, 4 figure

Current-Induced Step Bending Instability on Vicinal Surfaces

We model an apparent instability seen in recent experiments on current induced step bunching on Si(111) surfaces using a generalized 2D BCF model, where adatoms have a diffusion bias parallel to the step edges and there is an attachment barrier at the step edge. We find a new linear instability with novel step patterns. Monte Carlo simulations on a solid-on-solid model are used to study the instability beyond the linear regime.Comment: 4 pages, 4 figure