Publications - Publications

Nobelprisen går til...

Nielsen, K. H. — Mon, 01 Jan 2024 07:45:18 +0100

Mennesket ud af landbruget

Nielsen, K. H. — Fri, 28 Jun 2024 07:45:18 +0200

Hormoner eller ej

Nielsen, K. H. — Fri, 14 Jun 2024 07:45:18 +0200

Open Educational Resources on Open Science and Responsible Research and Innovation (Open RRI)

Lagido, C., Nielsen, K. H., Kragh, G., et al. — Mon, 01 Jan 2024 07:45:18 +0100

PreCareKlinikken – et borgerperspektiv

Eriksen, J., Eriksen, K., weber, D., Ebbesen, M., Nøhr, C. — Sun, 01 Jan 2023 07:45:18 +0100

Equity in digital healthcare – the case of Denmark

Eriksen, J., Ebbesen, M., KT, E., et al. — Sun, 01 Jan 2023 07:45:18 +0100

Artificial Intelligence Aided Ethics in Frontier Research

Lantada, A., Ebbesen, M. — Sun, 01 Jan 2023 07:45:18 +0100

Opening science to society

Wehn, U., Ajates, R., Mandeville, C., Somerwill, L., Kragh, G., Haklay, M. — Wed, 01 May 2024 07:45:18 +0200

A broad understanding of the aims and objectives of the international open science movement was recently adopted with the 2021 UNESCO Recommendation on Open Science, expanding the focus of open science to include scientific knowledge, infrastructures, knowledge systems and the open engagement of societal actors. In response, recent discussions on science policy practice are shifting to the implementation of open science via national policy. While policy instruments to support some aspects of open science are well-studied, guidance on the emerging 'social' aspects of open science has lagged, prompting UNESCO to generate guidance. In this paper, authors of a UNESCO Open Science Toolkit guidance document on 'Engaging societal actors in Open Science' synthesize the scholarly underpinnings behind the guidance document's recommendations. This work draws upon a targeted search from academic, policy, and grey literature in the fields of open science and community engagement, with a special focus on citizen science, to derive guidance on how to overcome barriers to the uptake of societal engagement approaches. The results present building blocks of what an enabling environment for the open engagement of societal actors could look like, identifying key considerations and reflecting on opportunities and challenges for progressing and evaluating sound open engagement of societal actors into regional & national (open) science policies.

Explanatory Stabilization in Situations of Evidential Uncertainty

Schindler, S. — Mon, 01 Jan 2024 07:45:18 +0100

Hvid dominans i jernstøberiet

Nielsen, K. H. — Wed, 08 May 2024 07:45:18 +0200

Einsteins problematiske Nobelpris

Nielsen, K. H. — Fri, 24 May 2024 07:45:18 +0200

Blitzkrig i haven

Nielsen, K. H. — Fri, 31 May 2024 07:45:18 +0200

Mastering the History of Pure and Applied Mathematics

Mon, 01 Jan 2024 07:45:18 +0100

Introducing the Philosophy of Mathematical Practice

Carter, J. — Mon, 01 Jan 2024 07:45:18 +0100

Fodbold er data

Nielsen, K. H. — Fri, 12 Apr 2024 07:45:18 +0200

Operation flere babyer

Nielsen, K. H. — Fri, 26 Apr 2024 07:45:18 +0200

Normal science

Schindler, S. — Mon, 01 Apr 2024 07:45:18 +0200

When Kuhn first published his Structure of Scientific Revolutions he was accused of promoting an “irrationalist” account of science. Although it has since been argued that this charge is unfair in one aspect or another, the early criticism still exerts an influence on our understanding of Kuhn. In particular, normal science is often characterized as dogmatic and uncritical, even by commentators sympathetic to Kuhn. I argue not only that there is no textual evidence for this view but also that normal science is much better understood as being based on epistemically justified commitment to a paradigm and as pragmatic in its handling of anomalies. I also argue that normal science is an example of what I call Kuhn’s program of revisionary rational reconstruction.

Predicting and describing the use of generative AI in science-related information search

Greussing, E., Guenther, L., Baram-Tsabari, A., et al. — Mon, 01 Apr 2024 07:45:18 +0200

Using Reference Publication Year Spectroscopy (RPYS) to analyze the research and publication culture in immunology

Wray, K. B., Paludan, S. R., Bornmann, L., Haunschild, R. — Sat, 01 Jun 2024 07:45:18 +0200

Reference Publication Year Spectroscopy (RPYS) is a method to reveal the historical roots and landmark papers of a research field based on cited references data. RPYS visualizes how frequently cited references occur in the cited reference lists of papers published in the research field. Previous RPYS studies revealed various historical aspects of the research and publication culture in various fields of study (e.g., economy and philosophy of science). Employing RPYS, we examine a dataset of citing publications in immunology. We identify and analyze 20 cited publications occurring very frequently in the cited reference lists of these citing papers. The 20 publications shed light on the epistemic culture and the development of the field of immunology. Whereas 65% of the publications were contributions to the theoretical and empirical understanding of immunology, 35% were contributions to methodology.

Fysikerne mellem videnskab og politik

Nielsen, H., Andersen, C. — Mon, 01 Apr 2024 07:45:18 +0200

Correction to

Bornmann, L., Wray, K. B., Haunschild, R. — Tue, 01 Sep 2020 07:45:18 +0200

In Bornmann, Wray, and Haunschild (2020, p. 1059), the term “like” was inadvertently included in the list of uncertainty terms. We did not use the term “like” for detection of uncertainty, and we did not intend to do so. The correct sentence should read: ‘The final set is as follows: “may”, “could”, “questions”, “might”, “potential”, “seems”, “perhaps”, “likely”, and “sometimes”.’ We apologize for any confusion this mistake might have caused.

Adapting to change: transforming research libraries into catalysts for citizen science in a rapidly evolving world

Nielsen, K. H., Kaarsted, T., Overgaard, A. K., Okholm, A. L., Martek, A. — Mon, 01 Jan 2024 07:45:18 +0100

Forskere mod abort

Nielsen, K. H. — Fri, 15 Mar 2024 07:45:18 +0100

Problemet med Central Park

Nielsen, K. H. — Wed, 27 Mar 2024 07:45:18 +0100

To the discerning reader: Galileo's philosophical comedy in a new translation

Nielsen, K. — Sun, 24 Mar 2024 07:45:18 +0100

Single, double and triple ionization of Ne, Ar, Kr and Xe by 30-1000 keV p^- impact

Paludan, K., Bluhme, H., Knudsen, H., et al. — Sun, 14 Sep 1997 07:45:18 +0200

Experimental data for single, double and triple ionization of Ne, Ar, Kr and Xe by 30-1000 keV antiproton impact are presented and compared with existing proton data. It is found that the current phenomenological understanding of ionization developed from studies of light targets generally apply to heavy atomic targets as well. Inner-shell ionization followed by Auger decay is found to be an important channel for multiple ionization of the heaviest targets, and the projectile charge dependence of their multiple ionization cross sections must be understood as stemming from the underlying inner-shell ionization cross sections.

Experimental investigation of photon multiplicity and radiation cooling for 150 GeV electrons/positrons traversing diamond and Si crystals

Kirsebom, K., Medenwaldt, R., Mikkelsen, U., et al. — Tue, 01 Oct 1996 07:45:18 +0200

Detailed experimental investigations of photon multiplicities for 150 GeV electrons/positrons traversing thin diamond and Si crystals have been performed. Along axial directions up to 10 photons are emitted in 1.5 mm diamond for a radiative energy loss larger than 4 GeV. This corresponds to a mean free path for photon emission of about two orders of magnitude shorter than in an amorphous target. This is in agreement with an enhanced radiative energy loss of ∼30 times that in amorphous targets. The strongly enhanced photon emission leads to radiation cooling which can result in particles exiting the crystal with a reduced angle to the axis. For incidences along planar directions the average multiplicity is still above one, even for the thinnest crystals used in the present experiment, so a single-photon spectrum can only be obtained for thicknesses ≤50 μm, which, on the other hand, is comparable to the coherence lengths for GeV photons, leading to destruction of the coherent effects.

Ionization in collisions between 30-1000 keV antiprotons and atomic hydrogen

Paludan, K., Charlton, M., Kirsebom, K., et al. — Mon, 01 Jan 1996 07:45:18 +0100

Recently published data for impact of antiprotons in the energy range 30-1000 keV on atomic hydrogen are compared with analogous proton, electron, and positron measurements, and it is found that the ionization cross sections of atomic hydrogen follow the same pattern as similar cross sections obtained on He and H₂ targets, in accordance with the general phenomenological description of single ionization that has developed over the last decade. Further comparisons are made with various recent and advanced theoretical calculations for antiproton ionization of atomic hydrogen. These theoretical results agree well with the data obtained, but for lower impact energies the different methods do not, despite the simplicity of the system, agree on predicting even the form of the cross section.

Ionization of rare gases by particle-antiparticle impact

Paludan, K., Laricchia, G., Ashley, P., et al. — Sun, 14 Sep 1997 07:45:18 +0200

New data for single and double ionization of the rare gases Ne, Ar, Kr and Xe, by positron and antiproton impact are presented and compared with existing data for electron and proton impact. It is found that the current understanding of these processes obtained from studies involving low-Z targets only extends to high-Z atoms provided that certain target-dependent effects are taken into consideration. In particular, the static interaction between the projectile and the undistorted target is found to play a crucial role in the case of the lighter projectiles.

Ionization of atomic hydrogen by 30-1000 keV antiprotons

Knudsen, H., Mikkelsen, U., Paludan, K., et al. — Sun, 01 Jan 1995 07:45:18 +0100

Ionization in collisions between antiprotons and atomic hydrogen is perhaps the least complicated and most fundamental process that can be treated by atomic-collision theory. We present measurements of the ionization cross section for 30-1000 keV antiprotons colliding with atomic hydrogen.

One and two electron processes in fast collisions between protons and hydrogen molecules

Fri, 05 May 1995 07:45:19 +0200

The ratio of double to single ionization of hydrogen molecules caused by fast proton impact was measured over a wide velocity range (v = 6-24 a.u.) using the coincidence time-of-flight technique. This ratio, ∼ 0.13% at high velocities, is about a factor of 2 smaller than the same ratio for the He target. This difference is due mainly to the larger single ionization cross section for hydrogen molecules, i.e. σ⁺(H₂) ∼ 2 σ⁺(He). The double ionization cross section, on the other hand, is similar for both He and H₂. Furthermore, the ratio of double to single ionization of the hydrogen molecule by proton impact is smaller than the one caused by electron impact at the same velocity in a similar way as for the helium target.

Measurement of the Barkas effect around the stopping-power maximum for light and heavy targets

Møller, S. P., Uggerhøj, E., Bluhme, H., et al. — Wed, 01 Jan 1997 07:45:19 +0100

The first direct measurements of antiproton stopping powers around the stopping power maximum are presented. The LEAR antiproton-beam of 5.9 MeV is degraded to 50-700 keV, and the energy-loss is found by measuring the antiproton velocity before and after the target. The antiproton stopping powers of Si and Au are found to be reduced by 30 and 40% near the electronic stopping power maximum as compared to the equivalent proton stopping power. The Barkas effect, that is the stopping power difference between protons and antiprotons, is extracted and compared to theoretical estimates.

Ionization of helium and molecular hydrogen by slow antiprotons

Hvefplund, P., Knudsen, H., Mikkelsen, U., et al. — Mon, 14 Mar 1994 07:45:19 +0100

Measurements of the cross sections for single and double ionization or helium as well as for the creation of H⁺₂ and H⁺ ions from H₂ for impact of antiprotons in the energy range 13-500 keV are presented. The results are compared with our earlier, less accurate data and with data for equivelocity proton impact. The single ionization cross section of helium agrees remarkably well with a continuum distorted wave (CDW-EIS) calculation. The ratio between the double and the single ionization cross sections of helium increases dramatically with decreasing projectile energy. New theoretical calculations are called for.

Non-dissociative single ionization of molecular hydrogen by electron and positron impact

Jacobsen, F. M., Frandsen, N. P., Knudsen, H., Mikkelsen, U. — Tue, 14 Nov 1995 07:45:19 +0100

Present experimental results for impact ionization of molecular hydrogen by electrons and positrons for the range of impact energies from threshold to about 2 keV (0.42 keV for e⁻). Our electron data agree with the most recent ones measured by others. When we compare our positron results to earlier published single ioniznrion cross sections we find significant differences for impact energies from threshold to about 100 eV with the new cross sections being substantially smaller. In the present study an effort has been made to discriminate against false signals caused by pasitronium formation and other effects.

Non-dissociative and dissociative ionization of O₂ molecules by impact of 40-1000 keV antiprotons

Bluhme, H., Knudsen, J., Mikkelsen, U., et al. — Wed, 01 Jan 1997 07:45:19 +0100

The non-dissociative single-ionization cross section for 40-1000 keV antiproton impact on O₂ molecules has been measured. Furthermore, the ratio between the production of O⁺ and O₂⁺ ions was obtained. The experimental results agree qualitatively with similar data obtained previously for other molecular targets, and support the 'standard picture' of ionization that has emerged during the last decade after much experimental as well as theoretical work on ionization caused by particles and their antiparticles.

Ionization and excitation of hydrogen molecules by fast proton impact

Ben-Itzhak, I., Krishnamurthi, V., Carnes, K. D., et al. — Mon, 01 Jan 1996 07:45:19 +0100

The ratio of ionization-excitation to single ionization of hydrogen molecules caused by fast proton impact was measured over a wide velocity range (v = 6-24 au) using the coincidence time-of-flight technique. This ratio, approx. 2%, is independent of the collision velocity at high velocities. It differs from the ratio of total H⁺ to H₂⁺ production mostly due to a large contribution from the dissociation of the electronic ground state of the molecular ion. The dissociation fraction of H₂⁺ (1sσ) was measured and compares well with our calculations using the Franck-Condon approximation.

Direct measurements of the stopping power for antiprotons of light and heavy targets

Møller, S. P., Uggerhøj, E., Bluhme, H., et al. — Wed, 01 Jan 1997 07:45:19 +0100

Measurements of antiproton stopping powers around the stopping-power maximum are presented for targets of Al, Si, Ti, Cu, Ag, Ta, Pt, and Au. The Low Energy Antiproton Ring antiproton beam of 5.9 MeV is degraded to 50–700 keV, and the energy loss is found by measuring the antiproton velocity before and after the target. Target thicknesses have been determined accurately by weighing and Rutherford backscattering techniques. The antiproton stopping powers are found to be reduced by around 35% for both light and heavy elements near the electronic stopping-power maximum as compared to the equivalent proton stopping power. The antiproton stopping powers and the Barkas effect; that is, the difference in stopping power between protons and antiprotons is compared to theoretical estimates, based on a harmonic-oscillator model and an electron-gas model, and good agreement is obtained.

Electron capture and ionization of 33-TeV Pb ions in gas targets

Krause, H. F., Vane, C. R., Datz, S., et al. — Thu, 01 Mar 2001 07:45:19 +0100

The total cross sections for electron capture and ionization of 33-TeV Pb ions in argon, krypton and xenon gas targets were measured. Electron capture from pair production dominates the total capture cross sections. The ionization cross sections from capture experiment (growth) and ionization experiment (decay) curves were compared. The results depicted the effective ionization cross sections in solid targets to be 25% larger than in gases for ionization experiment.

Månefeber

Nielsen, K. H. — Fri, 02 Feb 2024 07:45:19 +0100

Professorens prutter

Nielsen, K. H. — Fri, 16 Feb 2024 07:45:19 +0100

Scientific and philosophical publication

Wray, K. B. — Fri, 01 Mar 2024 07:45:19 +0100

Predictivism and avoidance of ad hoc-ness: an empirical study

Schindler, S. — Mon, 01 Apr 2024 07:45:19 +0200

Predictivism is the thesis that evidence successfully predicted by a scientific theory counts more (or ought to count more) in the confirmation of that theory than already known evidence would. One rationale that has been proposed for predictivism is that predictive success guards against ad hoc hypotheses. Despite the intuitive attraction of predictivism, there is historical evidence that speaks against it. As valuable as the historical evidence may be, however, it is largely indirect evidence for the epistemic attitudes of individual – albeit prominent – scientists. This paper presents the results of an empirical study of scientists’ attitudes toward predictivism and ad hoc-ness (n = 492), which will put the debate on a more robust empirical footing. The paper also draws attention to a tension between the ad hoc-ness avoidance rationale of predictivism and the ways philosophers have spelled out the notion of ad hoc-ness.

Beyond Footnotes: Lakatos's meta-philosophy and the history of science

Schindler, S. — Mon, 01 Jan 2024 07:45:19 +0100

AI kan få forskningen ud af elfenbenstårnet – men også misinformere masserne

Fuglsang, S., Fage-Butler, A., Nielsen, K. H. — Thu, 18 Jan 2024 07:45:19 +0100

Uro i sindet

Nielsen, K. H. — Fri, 05 Jan 2024 07:45:19 +0100

En slagplan mod wokeness

Nielsen, K. H. — Fri, 12 Jan 2024 07:45:19 +0100

Editorial

Boschiero, L., Wray, K. B. — Sun, 01 Mar 2015 07:45:19 +0100

David Oldroyd 1936–2014