Refine
Year of publication
Document Type
- Preprint (433)
- Article (240)
- Working Paper (3)
Language
- English (676)
Has Fulltext
- yes (676)
Is part of the Bibliography
- no (676)
Keywords
- Heavy Ion Experiments (14)
- Hadron-Hadron scattering (experiments) (11)
- Heavy-ion collision (6)
- LHC (5)
- ALICE experiment (3)
- Hadron-Hadron Scattering (3)
- Monetary Policy (3)
- Beauty production (2)
- Central Banking (2)
- Charm physics (2)
Institute
- Physik (672)
- Frankfurt Institute for Advanced Studies (FIAS) (616)
- Informatik (593)
- Center for Financial Studies (CFS) (3)
- Hochschulrechenzentrum (2)
- Biodiversität und Klima Forschungszentrum (BiK-F) (1)
- Geowissenschaften (1)
- House of Finance (HoF) (1)
- Senckenbergische Naturforschende Gesellschaft (1)
Correlations between moments of different flow coefficients are measured in Pb–Pb collisions at √sNN=5.02TeV recorded with the ALICE detector. These new measurements are based on multiparticle mixed harmonic cumulants calculated using charged particles in the pseudorapidity region |η| <0.8with the transverse momentum range 0.2 <pT<5.0GeV/c. The centrality dependence of correlations between two flow coefficients as well as the correlations between three flow coefficients, both in terms of their second moments, are shown. In addition, a collection of mixed harmonic cumulants involving higher moments of v2and v3is measured for the first time, where the characteristic signature of negative, positive and negative signs of four-, six-and eight-particle cumulants are observed, respectively. The measurements are compared to the hydrodynamic calculations using iEBE-VISHNU with AMPT and TRENTo initial conditions. It is shown that the measurements carried out using the LHC Run 2 data in 2015 have the precision to explore the details of initial-state fluctuations and probe the nonlinear hydrodynamic response of v2and v3to their corresponding initial anisotropy coefficients ε2and ε3. These new studies on correlations between three flow coefficients as well as correlations between higher moments of two different flow coefficients will pave the way to tighten constraints on initial-state models and help to extract precise information on the dynamic evolution of the hot and dense matter created in heavy-ion collisions at the LHC.
Long-range angular correlations on the near and away side in p–Pb collisions at √sNN=5.02 TeV
(2013)
Angular correlations between charged trigger and associated particles are measured by the ALICE detector in p–Pb collisions at a nucleon–nucleon centre-of-mass energy of 5.02 TeV for transverse momentum ranges within 0.5<pT,assoc<pT,trig<4 GeV/c. The correlations are measured over two units of pseudorapidity and full azimuthal angle in different intervals of event multiplicity, and expressed as associated yield per trigger particle. Two long-range ridge-like structures, one on the near side and one on the away side, are observed when the per-trigger yield obtained in low-multiplicity events is subtracted from the one in high-multiplicity events. The excess on the near-side is qualitatively similar to that recently reported by the CMS Collaboration, while the excess on the away-side is reported for the first time. The two-ridge structure projected onto azimuthal angle is quantified with the second and third Fourier coefficients as well as by near-side and away-side yields and widths. The yields on the near side and on the away side are equal within the uncertainties for all studied event multiplicity and pT bins, and the widths show no significant evolution with event multiplicity or pT. These findings suggest that the near-side ridge is accompanied by an essentially identical away-side ridge.
The lessons from QE and other 'unconventional' monetary policies - evidence from the Bank of England
(2011)
This paper investigates the effectiveness of the ‘quantitative easing’ policy, as implemented by the Bank of England in March 2009. Similar policies had been previously implemented in Japan, the U.S. and the Eurozone. The effectiveness is measured by the impact of Bank of England policies (including, but not limited to QE) on nominal GDP growth – the declared goal of the policy, according to the Bank of England. Unlike the majority of the literature on the topic, the general-to-specific econometric modeling methodology (a.k.a. the ‘Hendry’ or ‘LSE’ methodology) is employed for this purpose. The empirical analysis indicates that QE as defined and announced in March 2009 had no apparent effect on the UK economy. Meanwhile, it is found that a policy of ‘quantitative easing’ defined in the original sense of the term (Werner, 1994) is supported by empirical evidence: a stable relationship between a lending aggregate (disaggregated M4 lending, i.e. bank credit for GDP transactions) and nominal GDP is found. The findings imply that BoE policy should more directly target the growth of bank credit for GDP-transactions.
The unintended consequences of the debt ... will increased government expenditure hurt the economy?
(2011)
In 2008, governments in many countries embarked on large fiscal expenditure programmes, with the intention to support the economy and prevent a more serious recession. In this study, the overall impact of a substantial increase in fiscal expenditure is considered by providing a novel analysis of the most relevant recent experience in similar circumstances, namely that of Japan in the 1990s. Then a weak economy with risk-averse banks seemed to require some of the largest peacetime fiscal stimulation programmes on record, albeit with disappointing results. The explanations provided by the literature and their unsatisfactory empirical record are reviewed. An alternative explanation, derived from early Keynesian models on the ineffectiveness of fiscal policy is presented in the form of a modified Fisher-equation, which incorporates the recent findings in the credit view literature. The model postulates complete quantity crowding out. It is subjected to empirical tests, which were supportive. Thus evidence is found that fiscal policy, if not supported by suitable monetary policy, is likely to crowd out private sector demand, even in an environment of falling or near-zero interest rates. As a policy conclusion it is pointed out that by changing the funding strategy, complete crowding out can be avoided and a positive net effect produced. The proposed framework creates common ground between proponents of Keynesian views (as held, among others, by Blinder and Solow), monetarist views (as held in particular by Milton Friedman) and those of leading contemporary macroeconomists (such as Mankiw).
Central banks have recently introduced new policy initiatives, including a policy called ‘Quantitative Easing’ (QE). Since it has been argued by the Bank of England that “Standard economic models are of limited use in these unusual circumstances, and the empirical evidence is extremely limited” (Bank of England, 2009b), we have taken an entirely empirical approach and have focused on the QE-experience, on which substantial data is available, namely that of Japan (2001-2006). Recent literature on the effectiveness of QE has neglected any reference to final policy goals. In this paper, we adopt the view that ultimately effectiveness will be measured by whether it will be able to “boost spending” (Bank of England, 2009b) and “will ultimately be judged by their impact on the wider macroeconomy” (Bank of England, 2010). In line with a widely held view among leading macroeconomists from various persuasions, while attempting to stay agnostic and open-minded on the distribution of demand changes between real output and inflation, we have thus identified nominal GDP growth as the key final policy goal of monetary policy. The empirical research finds that the policy conducted by the Bank of Japan between 2001 and 2006 makes little empirical difference while an alternative policy targeting credit creation (the original definition of QE) would likely have been more successful.
Increasing atmospheric CO2 stimulates photosynthesis which can increase net primary production (NPP), but at longer timescales may not necessarily increase plant biomass. Here we analyse the four decade-long CO2-enrichment experiments in woody ecosystems that measured total NPP and biomass. CO2 enrichment increased biomass increment by 1.05 ± 0.26 kg C m−2 over a full decade, a 29.1 ± 11.7% stimulation of biomass gain in these early-secondary-succession temperate ecosystems. This response is predictable by combining the CO2 response of NPP (0.16 ± 0.03 kg C m−2 y−1) and the CO2-independent, linear slope between biomass increment and cumulative NPP (0.55 ± 0.17). An ensemble of terrestrial ecosystem models fail to predict both terms correctly. Allocation to wood was a driver of across-site, and across-model, response variability and together with CO2-independence of biomass retention highlights the value of understanding drivers of wood allocation under ambient conditions to correctly interpret and predict CO2 responses.