Relativistic fine structure oscillator strengths for Li-like ions: C IV - Si XII, S XIV, Ar XVI, Ca XVIII, Ti XX, Cr XXII, and Ni XXVI

Ab initio calculations including relativistic effects employing the Breit-Pauli R-matrix (BPRM) method are reported for fine structure energy levels and oscillator strengths upto n = 10 and 0.leq. l .leq.9 for 15 Li-like ions: C IV, N V, O VI, F VII, Ne VIII, Na IX, Mg X, Al XI, Si XII, S XIV, Ar XVI, Ca XIII, Ti XX, Cr XXII, and Ni XXVI. About one hundred bound fine structure energy levels of total angular momenta, 1/2 .leq. J .leq. 17/2 of even and odd parities, total orbital angular momentum, 0 .leq L .leq. 9 and spin multiplicity (2S+1) = 2, 4 are considered for each ion. The levels provide almost 900 dipole allowed and intercombination bound-bound transitions. The BPRM method enables consideration of large set of transitions with uniform accuracy compared to the best available theoretical methods. The CC eigenfunction expansion for each ion includes the lowest 17 fine structure energy levels of the core configurations 1s^2, 1s2s, 1s2p, 1s3s, 1s3p, and 1s3d. The calculated energies of the ions agree with the measured values to within 1% for most levels. The transition probabilities show good agreement with the best available calculated values. The results provide the largest sets of energy levels and transition rates for the ions and are expected to be useful in the analysis of X-ray and EUV spectra from astrophysical sources.Comment: 16 pgs., to appear in Astronomy and Astrophysic

Educational differences in fertility desires, intentions and behaviour: a life course perspective

Despite a long tradition of studying the relationship between education and fertility outcomes less is known about how educational differences in fertility intentions are formed and translated into achieved births over the life course. This paper provides new insights using data from a large cohort study and Miller’s Traits-Desires-Intentions-Behaviour framework for understanding childbearing. We examine how parental aspirations for education, educational ability in childhood, and educational attainment in young adulthood relate to: males’ and females’ fertility desires in adolescence; fertility intentions in early adulthood; and educational differences in the achievement of fertility intentions. We conclude that family building preferences expressed in adolescence, especially those for the timing of entry into parenthood are shaped by parental socio-economic background, mediated through educational ability and parental expectations for education. In young adulthood, no clear, consistent educational gradient in intended family size is found. However, there is a negative educational gradient in the likelihood of achieving intended births by age 46, especially for women. The findings indicate the importance of educational differences in employment and partnership behaviour in mediating these relationships

New insights into the fertility patterns of recent Polish migrants in the United Kingdom

There have been important changes in the United Kingdom’s (UK) fertility and immigration in the past decade, with a large share contributed by migrants from Poland. A detailed understanding of Polish migrant fertility is lacking, however, because the relevant data are not routinely collected. This paper provides new insights into the fertility patterns of Polish migrants in the UK, and compares these patterns with those of other large immigrant groups, the UK-born population and with patterns in Poland. We use the UK Labour Force Survey with the Own Child(ren) Method, illustrating the potential of survey data for estimating immigrant fertility in settings where other data are unavailable. We first compare the fertility patterns of recent Polish migrants with those of other key recent immigrant groups and the UK-born population; estimating: 1) Age-Specific Fertility Rates (ASFRs), and Total Fertility Rates (TFRs), by country of birth for the 2004-2012 period, 2) The proportions in each immigrant group that arrive without children, and, 3) Of those childless at arrival the proportions of women who go on to have births within a short period of arrival. Next, we compare the ASFRs and TFR for Polish migrant women with those observed in Poland. Our results show that the fertility of Polish migrants is amongst the lowest for all population subgroups in the UK, and that Polish migrants are less likely to have children soon after arrival than other immigrant groups. The findings are consistent with migration not being so closely linked to family formation for Polish migrants as it is for immigrants in the comparison groups. We also find that the fertility patterns of Polish migrants are different to those observed in Poland with a later childbearing profile and a slightly higher TFR

Economic precariousness and living in the parental home in the UK

Today’s young adults are facing increased economic uncertainty as a result of unemployment, the continued growth of low-paid, insecure and often part-time employment, accelerated by the recent economic downturn. Recent media attention has focused on the trend for increased co-residence of adult children with their parent(s). It is generally assumed that this trend relates directly to the increased economic uncertainty of young adults, combined with the challenges of affordability in the housing market. This research is motivated by the need to identify which groups are most at risk of economic uncertainty and to investigate the consequences for young adults’ abilities to make successful transitions to adulthood. The paper contributes to the literature on both youth employment and housing transitions and the intersection of both. The aim of the paper is three fold: 1) To explore how different aspects of precariousness (labour market insecurity, employment insecurity, and income insecurity) can be operationalised using quantitative data; 2) To use these indicators to provide estimates of precarity amongst young men and women aged 18-34; 3) To examine how these indicators are related to the likelihood of living in the parental home. We use data from the first wave of the United Kingdom Household Longitudinal Study (UKHLS) which was conducted in 2009/10, at the height of the economic downturn. By disaggregating analyses by gender and age we get beneath aggregate summary statistics and provide new insights into how young people’s experience of employment changes across the transition from older teenager, to those in their twenties and for those in their early thirties. The survey data suggest considerable income inequalities between young adults. Not surprisingly, the unemployed and economically inactive are concentrated in the lowest income quartiles. Among employed young adults, income levels differ significantly according to the hours worked, and occupational status. Our analyses show that young people are over-represented in routine and semi-routine jobs, most of these jobs tend to be low-paid and are in the bottom income quartile. Whilst the proportion in routine and semi-routine jobs decreases with age as young people gain the necessary skills and experience to climb the occupational ladder, a sizeable proportion – about one in five men and women in their early thirties remain in a routine or semi-routine job.A significant minority of young adults are self-employed. Among this group, we find a bi-modal income distribution, suggesting that for some, self-employment is an entrepreneurial success story. However, over one half of the self-employed in their late twenties and early thirties are in the lowest quartile suggesting that for others, self-employment is a new form of precarity. This research also quantifies the extent to which different indicators of precarity are related. We find that young adults often face multiple dimensions of economic precarity. For example, male part-time workers tend to have lower personal incomes, and part-time work is associated with being on a temporary contract and being in semi-routine or routine jobs. Almost all the indicators of precariousness were found to be associated with a higher likelihood of living in the parental home, suggesting that these young adults face constraints on their ability to make the transition to residential independence. Some differences are seen according to age. For men and women aged under 25, both unemployment, being temporary or part-time employed, or being in a (semi)routine job are associated with a higher likelihood of remaining in the parental home. By their late twenties only a small proportion of women, but a higher proportion of men remain living with their parents. At these ages, it is unemployed and economically inactive and men in (semi) routine jobs, and men with lower levels of personal income who are significantly more likely to remain living with their parent(s). This research has implications for various actors including national and local government, housing agencies and employee groups as well as the self-employed. Young adults are concentrated in parts of the economy dominated by zero and short-hours contracts and governments should regulate these types of contracts. In addition, uncertainties associated with self-employment need to be recognised since they may have implications for making stable housing and family transitions. New policies need to consider the groups struggling most with housing costs; young single people, especially those without children, who are renting single bedroom properties, particularly in London. Furthermore, policies need to be developed to support pay and skills progression among young adults.<br/

Measuring economic precarity among UK youth during the recession

What are the key aspects of economic precariousness and which are most relevant to analysing young people’s lives? In this study we use data from the United Kingdom Household Longitudinal Study (UKHLS) to identify the proportion of men and women aged 18-34 who might be considered to be in an economically precarious situation and investigate how the dimensions of precariousness are interrelated. This paper summarises findings from the CPC Working Paper 55

Educational aspirations among UK young teenagers: exploring the role of gender, class and ethnicity

This paper presents an overview of teenagers’ aspirations for higher levels of education during the recent economic recession. We analyse the responses of 4899 young people aged 10 to 15, who participated in the UK Household Longitudinal Study in 2009-10. The timing of the survey is especially significant given the political emphasis on raising aspirations as a means to stimulate the economy. We consider the impact of gender, parental occupational class, parental educational background, family structure and parental attitudes towards education upon teenagers’ educational aspirations, and use multiple regression analyses to consider whether their effects are consistent across ethnic groups. Until now, only limited nationally representative data on young people’s aspirations have been available, especially in respect of ethnic differences. This research aims to fill that gap. It was undertaken as part of a wider study into the aspirations for living and learning among young people in the UK

Electron impact on K+: mechanisms for extreme ultraviolet submission

A series of R-matrix calculations on K+ is used to derive electron excitation and ionization cross sections. The excitation cross section to the 4s and 3d levels leading to the K+ 60.1, 60.8 and 61.3nm emission lines shows poor agreement with the cross beam experiment of Zapesochny et al (1986, Zh. Eksp. Teor. Fiz. 90 1972 [Sov. Phys. JETP 63 1155]). Cross sections are also presented for exciting the 4p, 5s and 4d levels, the autoionizing 3s open-shell levels, and for ionization. It is shown how pseudoresonances in the calculated cross section can be eliminated by increasing the target basis.</p

Childlessness in the UK

Levels of childlessness in Britain are high in comparison with many other European countries, with just under one in five women currently reaching age 45 with no biological children of their own. This chapter provides new insights in two ways: First we combine childbearing data from repeated rounds of the General Household Survey and United Kingdom Household Panel Survey to identify how childlessness has increased at a similar rate among all educational groups, but that levels remain far higher among women with academic degree-level education. Secondly, the paper examines childlessness from a life course perspective among men and women born in 1970 who have been followed up within the British Cohort Study. Focusing on cohort members who were childless at age 30, we examine the relationship between fertility intentions expressed at age 30 and achieved childbearing by age 42. At age 42, those men and women who remained childless were invited to give their reasons for remaining childless. Some report that they did not have children 'due to health reasons', many more responded that they 'did not ever want children', whilst others said that they had 'not met the right partner to have children with'. Only a few suggested that they 'had been focused on their career'. We examine these responses in the context of the individual's partnership history and contribute to the debate as to whether the 'perpetual postponement' of childbearing to later ages is acting to increase the proportion who ultimately remain childles