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The Forward Physics Facility (FPF) is a proposed new facility to house several new experiments at the CERN High Luminosity LHC (HL-LHC). The FPF is located such that the experiments can be aligned with the collision axis line of sight (LOS), a location which allows many interesting physics measurements and searches for new physics to be carried out. The status of technical studies related to the FPF, as well as the physics potential were documented in Ref. [1] which was released in March 2022. This note documents updates to the FPF technical studies completed since that time.

The BDF/SHiP collaboration has proposed a general-purpose intensity-frontier experimental facility operating in beam-dump mode at the CERN SPS accelerator to search for feebly interacting GeV-scale particles and to perform measurements in neutrino physics. BDF/SHiP complements the world-wide program of New Physics searches by exploring a large region of parameter space which cannot be addressed by other experiments, and which reaches several orders of magnitude below existing bounds. The SHiP detector is sensitive both to decay and scattering signatures of models with heavy neutral leptons, dark photons, dark scalars, axion-like particles, light dark matter and other feebly interacting particles. In neutrino physics, BDF/SHiP can perform unprecedented measurements with tau neutrinos and neutrino-induced charm production. Following the Technical Proposal submitted in 2015, the subsequent three-year Comprehensive Design Study (CDS), and the recent study of BDF/SHiP in existing beam facilities around the SPS, this paper restates the motivation and reports on the implementation and physics performance of BDF/SHiP in the SPS ECN3 high-intensity beam facility.

As part of the main focus of the BDF Working Group in 2021, this document reports on the study of alternative locations and possible optimisation that may accompany the reuse of existing facilities with the aim of significantly reducing the costs of the facility. Building on the BDF/SHiP Comprehensive Design Study (CDS), the assessment rests on the generic requirements and constraints that allow preserving the physics reach of the facility by making use of the $4\times 10^{19}$ protons per year at 400\,GeV that are currently not exploited at the SPS and for which no existing facility is compatible. The options considered involve the underground areas TCC4, TNC, and ECN3. Recent improvements of the BDF design at the current location (referred to as `TT90-TCC9-ECN4') are also mentioned together with ideas for yet further improvements. The assessments of the alternative locations compiled the large amount of information that is already available together with a set of conceptual studies that were performed during 2021. As part of the main focus of the BDF Working Group in 2021, this document reports on the study of alternative locations and possible optimisation that may accompany the reuse of existing facilities with the aim of significantly reducing the costs of the facility. Building on the BDF/SHiP Comprehensive Design Study (CDS), the assessment rests on the generic requirements and constraints that allow preserving the physics reach of the facility by making use of the $4\times 10^{19}$ protons per year at 400 GeV that are currently not exploited at the SPS and for which no existing facility is compatible. The options considered involve the underground areas TCC4, TNC, and ECN3. Recent improvements of the BDF design at the current location (referred to as `TT90-TCC9-ECN4') are also mentioned together with ideas for yet further improvements. The assessments of the alternative locations compiled the large amount of information that is already available together with a set of conceptual studies that were performed during 2021. The document concludes with a qualitative comparison of the options, summarising the associated benefits and challenges of each option, such that a recommendation can be made about which location is to be pursued. The most critical location-specific studies required to specify the implementation and cost for each option are identified so that the detailed investigation of the retained option can be completed before the end of 2022.

PURPOSE: The aim of this pilot study was to investigate the initial effect of contact lens wear on spontaneous blink characteristics.METHODS: This was a randomised, crossover pilot study. Spontaneous blinking was recorded using a high-speed infrared camera in ten subjects with three different soft contact lenses (spherical hydrogel, spherical silicone hydrogel and toric hydrogel), one rigid contact lens and without contact lenses. Custom semi-automated software was used to determine palpebral aperture height, interblink interval (IBI), blink speed, blink completeness and blink duration.RESULTS: The IBI was significantly greater for non-lens wear compared with the silicone hydrogel [ratio (95% CI): 1.34 (1.16, 1.55), p < 0.0001], toric hydrogel [1.28 (1.10, 1.48), p = 0.0001] and rigid corneal lenses [1.48 (1.27, 1.73), p < 0.0001]. The spherical silicone hydrogel lens showed greater closing-phase speed than non-lens wear [mean difference (95% CI): 27.4 (5.6, 49.1) mm/s, p = 0.006]. Shorter total blink duration was found for non-lens wear compared with any of the lens types [spherical hydrogel: ratio 0.89 (0.81, 0.98), p = 0.01; spherical silicone hydrogel: 0.87 (0.80, 0.95), p = 0.0001; toric hydrogel: 0.90 (0.83, 0.98), p = 0.004; and rigid corneal: 0.88 (0.82, 0.96), p = 0.0004]. Opening-phase speed (p = 0.12) and blink completeness metrics (all p > 0.5) were not influenced by wearing condition.CONCLUSION: This work showed that short-term contact lens wear influenced the palpebral aperture height, IBI, speed and duration of the blink, and the effect is dependent on the contact lens type. The completeness of the blink was not altered by contact lens wear. Future work should be conducted to assess the effect of long-term wear of different contact lens types on blink characteristics. The measurement of spontaneous blinking characteristics represents an immediate, sensitive and non-invasive evaluation of the impact of a contact lens on the ocular surface.

Purpose: To test the hypothesis that various subjective ocular and task-related parameters associated with wearing a face mask would be better in neophyte contact lens (CL) wear compared to habitual spectacle (Sp) wear. Methods: Thirty participants were randomised to continue in Sp (n = 15) or wear somofilcon A daily disposable CL (n = 15) (‘group’). A surgical face mask (Type II R) was worn for at least one hour per day on four or more days per week. After two weeks, participants completed the Quality of Life Impact of Refractive Correction Questionnaire (QIRC), a two-part face mask usability questionnaire and graded ocular-related symptoms using 0–100 visual analogue scales. Results: There was no difference between groups for overall QIRC score but some individual question scores reflected better quality of life in the CL: ‘outdoor activities’, ‘keep fit’ and ‘able to do things’ (all p < 0.05). Differences in favour of the CL were seen for the following in the face mask usability questionnaire: ‘breathing’, ‘heat’, ‘comfort on ears’, ‘overall comfort’, ‘walking’, ‘driving’, ‘reading’, ‘computer use’, ‘exercising’ and ‘socialising’ (all p < 0.05). Significant differences were also seen for the 0–100 VAS symptoms probing vision quality in favour of the CL: glare, distance and near vision, fogging, restricted field of view and peripheral blur. Conclusion: This work supports anecdotal reports that CL are a better vision correction option than Sp when used in conjunction with a face mask. Participants reported a range of benefits to the CL/face mask combination for vision-related symptoms, breathing and heat-related symptoms and a number of day-to-day activities including walking, driving and exercising. All of the benefits relating to the CL are likely to result in improved adherence to face mask use. Overall, the findings of this work suggest that where possible, CL should be the preferred vision correction option for people using face masks.

This paper outlines changes to the ocular surface caused by contact lenses and their degree of clinical significance. Substantial research and development to improve oxygen permeability of rigid and soft contact lenses has meant that in many countries the issues caused by hypoxia to the ocular surface have largely been negated. The ability of contact lenses to change the axial growth characteristics of the globe is being utilised to help reduce the myopia pandemic and several studies and meta-analyses have shown that wearing orthokeratology lenses or soft multifocal contact lenses can reduce axial length growth (and hence myopia).However, effects on blinking, ptosis, the function of Meibomian glands, fluorescein and lissamine green staining of the conjunctiva and cornea, production of lid-parallel conjunctival folds and lid wiper epitheliopathy have received less research attention. Contact lens wear produces a subclinical inflammatory response manifested by increases in the number of dendritiform cells in the conjunctiva, cornea and limbus. Papillary conjunctivitis is also a complication of all types of contact lenses. Changes to wear schedule (daily disposable from overnight wear) or lens materials (hydrogel from SiHy) can reduce papillary conjunctivitis, but the effect of such changes on dendritic cell migration needs further study. These changes may be associated with decreased comfort but confirmatory studies are needed. Contact lenses can affect the sensitivity of the ocular surface to mechanical stimulation, but whether these changes affect comfort requires further investigation.In conclusion, there have been changes to lens materials, design and wear schedules over the past 20+ years that have improved their safety and seen the development of lenses that can reduce the myopia development. However, several changes to the ocular surface still occur and warrant further research effort in order to optimise the lens wearing experience.

Purpose This work set out to investigate if there was an association between subjective comfort and both subjective and measured vision during the use of contemporary daily disposable soft toric contact lenses. Methods Thirty-eight habitual soft contact lens wearers wore each of three daily disposable toric lenses for one week in a prospective, crossover, randomised, single-masked study. The following clinical measures were recorded at dispensing and follow-up visits: biomicroscopy scores, lens fitting (including rotation and rotational stability), high and low contrast visual acuity, subjective vision quality and subjective ocular surface comfort. Subjective scores were collected using 0–10 numerical grading scales. Comfort scores were analysed using a linear regression model with age, sex, visit, phase of crossover (‘phase’), lens type, lens rotation, lens rotational stability, visual acuity, cylinder power and subjective vision quality as factors of interest and then refined using backward stepwise regression. Results Thirty six participants (31.1 ± 13.5 years) completed the study. Comfort scores were found to be associated with subjective vision quality (F = 127.0 ; p < 0.0001), phase (F = 7.2; p = 0.001) and lens type (F = 4.9; p = 0.009). Greater comfort scores were observed with greater subjective vision quality scores. Visual acuity was not statistically significant in the model. Conclusion This work suggests that symptoms of ocular discomfort may be more intense if there is also perceived visual compromise in daily disposable soft toric lenses. There was a stronger positive correlation between comfort and subjective vision quality compared with comfort and measured visual acuity.

PURPOSE Development and validation of a non-invasive imaging system to capture spontaneous blinking and characterise blink dynamics using a custom image analysis algorithm. METHODS A pilot study investigated the influence of illumination type on blink dynamics. Spontaneous blinking was recorded in eight subjects using a high-speed camera under two illumination conditions: white light and infrared. Custom semi-automated software assessed palpebral aperture height (PAH), blink rate, blink speed, blink completeness and blink duration. The main clinical study compared two different image analysis techniques. Spontaneous blinking was recorded in 20 subjects using a high-speed infrared camera. Blink speed and duration were determined using two techniques: manual tracking and semi-automated tracking. Agreement between the two techniques was assessed using Bland-Altman analysis. Coefficients of repeatability (COR) were calculated for the semi-automated technique. RESULTS There were significant differences between white light and infrared illumination for PAH (p

PurposeTo investigate ocular discomfort during contact lens wear using a wrist-mounted electronic ‘lens awareness logger’ (LAL).MethodsThirty symptomatic contact lens wearers wore study contact lenses for three days. On the first two days, two lens types which are known to differ in end-of-day comfort (lens A: senofilcon A and lens B: balafilcon A), were worn as a matching pair (randomised order). On day three, a pair of lens B was worn. On each day, the participant used a LAL. On day one and two, the participant pressed a button on the LAL whenever they became aware of their lenses due to discomfort. On day three, the participant used a multiple click protocol (1 = mild awareness to 3 = severe awareness) to report discomfort.ResultsLAL events were similar on days one and two (17.3 vs. 15.8 events per day). There were significantly more LAL events for lens B (21.6 events per day) in comparison with lens A (11.6 events per day) (p = 0.006). The LAL event profile highlighted peaks in awareness following lens application and towards the end of the wearing cycle. Comparison of the LAL event profile for the two lens types showed significant differences in lens awareness, particularly in the first half of the wearing cycle. LAL events on day 3, showed a uniform distribution of single and double clicks through the day, but a marked peak in triple clicks in the last two hours of lens wear.ConclusionThe LAL was able to differentiate between the study lenses and demonstrated differences in their LAL event profiles. Lens awareness associated with discomfort appeared to increase not only in frequency, but also in intensity towards the end of the wearing cycle. The ability of the LAL to track lens awareness suggests it is likely to be a useful tool in furthering understanding of ocular discomfort.

Purpose: Fluorescein-labelled wheat germ agglutinin (F-WGA) acts as a marker for ocular surface mucins. This clinical study sought to investigate whether the degree of F-WGA fluorescence observed at the ocular surface differed between symptomatic contact lens wearers, asymptomatic contact lens wearers and non-contact lens wearers, using a novel imaging system. Methods: Twenty-five participants (10 symptomatic contact lens wearers, 10 asymptomatic contact lens wearers and 5 non-contact lens wearers) attended a single study visit. Photographs of the cornea, bulbar and tarsal conjunctiva were captured following application of F-WGA solution. Results: The imaging system captured high-resolution images of F-WGA fluorescence at the ocular surface. The degree of fluorescence differed between the ocular surface regions (p

PURPOSE:: The aim of this study was to map the sensitivity of the marginal and other conjunctival regions and to investigate changes in the sensitivity of these regions when determined in the morning and evening. METHODS:: Thirty-five healthy, noncontact lens wearers (20 female, 15 male; age 27.7 ± 7.3 years) were enrolled. Mechanical sensitivity was measured at 8 locations on the ocular surface and adnexa (cornea, marginal, bulbar, and tarsal conjunctiva) using a Cochet-Bonnet esthesiometer (0.12-mm diameter filament). A subgroup of 11 subjects (6 female, 5 male; age 28.9 ± 9.9 years) returned after 12 hours when this protocol was repeated. RESULTS:: The cornea was found to be the most sensitive region (all P 0.05). The upper tarsal conjunctiva was more sensitive than the lower tarsal conjunctiva (P = 0.04). There was no significant difference in the sensitivity determined in the morning and the evening for any of the locations investigated (Bonferroni adjusted, P > 0.006). CONCLUSIONS:: This work has demonstrated that the marginal conjunctiva was the most sensitive of all the conjunctival regions and that this does not alter over the course of the day. Copyright © 2014 by Lippincott Williams & Wilkins.

Objectives: To measure various dimensions of the upper tarsal plate and the area of upper lid wiper staining. The repeatability of the method of measurement was investigated.Methods: Thirty-five healthy non–contact lens wearers were enrolled. The following parameters were measured from digital images of the upper eye- lid captured with a slitlamp camera: length, height, and total area of the tarsal plate and area of lid wiper staining (lissamine green). Measurements were performed in a randomized and masked fashion on two separate occasions by the same investigator using ImageJ (National Institutes of Health). Coefficients of repeatability (COR) were calculated.Results: The dimensions (mean6SD) of the tarsal plate were 20.661.9 mm length, 7.960.8 mm height, and 103.3618.8 mm2 total area. The area of lid wiper staining was 2.762.0 mm2. No association was found between tarsal dimensions and lid wiper staining (all P.0.05). Image analysis COR values were 0.6 mm tarsal length, 0.1 mm tarsal height, 1.2 mm2 tarsal area, and 0.4 mm2 lid wiper staining. There was no significant difference between repeated measurements for any parameter (all P.0.05). Limits of agree- ment were narrow for all parameters, indicating good agreement between repeated measurements.Conclusions: This work has demonstrated that there is a wide range in the dimensions of the upper tarsal plate in an urban UK population. No association was found between the upper tarsal dimensions and lid wiper staining. ImageJ was shown to be a repeatable method to measure the dimensions of the upper tarsal plate and upper lid wiper staining.

PURPOSE: To map the sensitivity and staining of the marginal conjunctiva in soft contact lens (SCL) wearers and nonwearers and to investigate diurnal changes. METHODS: Thirty-five nonwearers and 35 SCL wearers were recruited. Mechanical sensitivity was measured at 8 locations on the ocular surface and adnexa (cornea, marginal, bulbar, and tarsal conjunctivae) using the Cochet-Bonnet aesthesiometer. Lid margin staining (lissamine green) was assessed through image analysis. Measurements were repeated at 12 hours in 11 nonwearers and 10 symptomatic SCL wearers. RESULTS: The marginal conjunctiva was the most sensitive conjunctival region (all P 0.05). There was a significant difference in sensitivity between the 2 groups in the morning for the lower lid tarsal conjunctiva (P = 0.003). After 12 hours, the sensitivity of the lower lid marginal conjunctiva was found to be reduced in SCL wearers compared with nonwearers (all P

Purpose To investigate whether carrying out various interventions part way through the day influences comfort in symptomatic daily disposable (DD) contact lens wearers. Methods A subject-masked, randomized, controlled clinical trial was conducted in thirty symptomatic soft lens wearers who wore their habitual DD contact lenses bilaterally for 12 h on two separate days. Five hours after lens application, one of the following three interventions or a control was performed on each eye: replacing the existing lens with a new lens; removing and reapplying the same lens; performing a ‘scleral swish’; and no action (control). Comfort scores were recorded using SMS text messages every hour following lens application using a 0 (causes pain) to 100 (excellent comfort) scale. Comfort scores before lens application, at 6 mins post-application, and at 6 mins post-intervention were also recorded. Results There was a significant reduction in comfort from pre-lens application to 6 mins post-application for all groups (all p0.05). After the intervention, comfort continued to decline (p

Purpose: The aim of this study was to map the sensitivity of the marginal and other conjunctival regions and to investigate changes in the sensitivity of these regions when determined in the morning and evening. Methods: Thirty-five healthy, noncontact lens wearers (20 female, 15 male; age 27.7 6 7.3 years) were enrolled. Mechanical sensitivity was measured at 8 locations on the ocular surface and adnexa (cornea, marginal, bulbar, and tarsal conjunctiva) using a Cochet– Bonnet esthesiometer (0.12-mm diameter filament). A subgroup of 11 subjects (6 female, 5 male; age 28.9 6 9.9 years) returned after 12 hours when this protocol was repeated. Results: The cornea was found to be the most sensitive region (all P , 0.001). The marginal conjunctiva showed greater sensitivity than did the bulbar and tarsal conjunctiva (all P , 0.001). The temporal marginal conjunctiva was more sensitive than the central marginal conjunctiva (all P , 0.05). No difference in marginal con- junctival sensitivity was found between upper and lower eyelids (all P . 0.05). The upper tarsal conjunctiva was more sensitive than the lower tarsal conjunctiva (P = 0.04). There was no significant differ- ence in the sensitivity determined in the morning and the evening for any of the locations investigated (Bonferroni adjusted, P . 0.006). Conclusions: This work has demonstrated that the marginal conjunctiva was the most sensitive of all the conjunctival regions and that this does not alter over the course of the day.

Purpose: To map the sensitivity of the marginal and tarsal conjunctiva of upper and lower eyelids in a group of noncontact lens wearers and to compare the sensitivity of these areas with the sensitivity of the central cornea and bulbar conjunctiva. This work also investigated whether the sensitivity of these areas changed over the course of the day. Method: Thirty-five healthy non-contact lens wearers (20 female, 15 male; age 27.7±7.3 years) were enrolled. Mechanical sensitivity was measured at various locations on the ocular surface (cornea, lid wiper, bulbar and tarsal conjunctiva) using a Cochet-Bonnet aesthesiometer (0.12mm diameter thread). Lid wiper epitheliopathy (LWE) stainingusing lissaminegreenwasalso recorded by analysing digital images using Image J (NIH). These measurements were performed in the morning in all subjects and 12hours later in 11 subjects. Results: The cornea was found to be the most sensitive region (p 0.05). LWE staining was greater for the lower eyelid compared to the upper eyelid (p =0.003). No significant change was found in LWE over time (p>0.05). There was no association between sensitivity and LWE staining (all p >0.05). Conclusions: Thiswork has demonstrated that the sensitivity of the lid wiper area was greater than other conjunctival areas. There was no significant change in either sensitivity or LWE staining over the course of a day. Additionally, LWE staining was higher for the lower eyelid compared to the upper eyelid.